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      contextRef="FY2022_S000003863Member_C000010829Member"
      decimals="4"
      id="h_592de917_1157_4044_a1ee_e1587d01839b"
      unitRef="pure">-0.1576</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2023_S000003863Member_C000010829Member"
      decimals="4"
      id="h_8f8c5ba3_61db_4f82_b786_b3f826eee0e4"
      unitRef="pure">0.1656</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2021_S000003863Member_C000010829Member"
      decimals="4"
      id="h_901a196f_6444_440d_b474_a1096e71ff99"
      unitRef="pure">0.1665</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2016_S000003863Member_C000010829Member"
      decimals="4"
      id="h_94b1aba0_aeb1_421e_a72a_12913a298ca8"
      unitRef="pure">0.0865</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2018_S000003863Member_C000010829Member"
      decimals="4"
      id="h_af9e6086_15a1_44a0_8c4f_4f1cc6556d7f"
      unitRef="pure">-0.0266</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2020_S000003863Member_C000010829Member"
      decimals="4"
      id="h_b0e7aff9_be45_403e_8e52_7cc5e34d1375"
      unitRef="pure">0.1575</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2024_S000003863Member_C000010829Member"
      decimals="4"
      id="h_d2cbfd06_b0d2_41fd_a519_ef1609d3369c"
      unitRef="pure">0.1288</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2025_S000003863Member_C000010829Member"
      decimals="4"
      id="h_f19b50f9_4744_4483_9538_19201a295482"
      unitRef="pure">0.1567</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2022_S000003867Member_C000010833Member"
      decimals="4"
      id="h_00e033e0_2141_464a_941d_e2b73f196b44"
      unitRef="pure">-0.3759</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2019_S000003867Member_C000010833Member"
      decimals="4"
      id="h_0ade2300_91e8_4eda_ac2d_a13b9d150683"
      unitRef="pure">0.3279</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2023_S000003867Member_C000010833Member"
      decimals="4"
      id="h_157b5fb7_78ec_4346_b6e6_811917589688"
      unitRef="pure">0.4960</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2020_S000003867Member_C000010833Member"
      decimals="4"
      id="h_15d37dd4_56c4_4376_84c2_e0df1f347242"
      unitRef="pure">0.4016</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2018_S000003867Member_C000010833Member"
      decimals="4"
      id="h_1d6730ad_24e0_43f5_bd03_d8ac71d9a52a"
      unitRef="pure">0.0242</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2021_S000003867Member_C000010833Member"
      decimals="4"
      id="h_3b337b3c_42f0_4920_b8d3_306fd4a0f5b2"
      unitRef="pure">0.2122</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2024_S000003867Member_C000010833Member"
      decimals="4"
      id="h_43b4c595_6e6f_47f7_b225_ce33a15a9e2d"
      unitRef="pure">0.3149</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2016_S000003867Member_C000010833Member"
      decimals="4"
      id="h_59464835_6873_4a1e_99ec_37747da46ab8"
      unitRef="pure">0.0040</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2017_S000003867Member_C000010833Member"
      decimals="4"
      id="h_a9062a38_5926_4d03_8d55_1cfd946f9aee"
      unitRef="pure">0.3362</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2025_S000003867Member_C000010833Member"
      decimals="4"
      id="h_d67dea78_6948_47e2_8554_baa7a76c50bf"
      unitRef="pure">0.1204</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2021_S000003866Member_C000010832Member"
      decimals="4"
      id="h_11b994ee_107a_488f_a932_bb737b2b42f1"
      unitRef="pure">0.0679</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2025_S000003866Member_C000010832Member"
      decimals="4"
      id="h_153e9b9a_ebf9_4ce0_a765_a780e14eaad4"
      unitRef="pure">0.1961</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2019_S000003866Member_C000010832Member"
      decimals="4"
      id="h_40f6d2aa_9b26_45d2_bcce_868054ef2af2"
      unitRef="pure">0.1805</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2020_S000003866Member_C000010832Member"
      decimals="4"
      id="h_512130b1_8252_4a60_ab70_be00ba1101d7"
      unitRef="pure">0.2095</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2024_S000003866Member_C000010832Member"
      decimals="4"
      id="h_82a95351_d981_44c0_9d22_64235d8bd655"
      unitRef="pure">0.0967</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2016_S000003866Member_C000010832Member"
      decimals="4"
      id="h_a4286e7d_7c7c_49db_92f9_fe910e63e821"
      unitRef="pure">0.0417</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2018_S000003866Member_C000010832Member"
      decimals="4"
      id="h_b07528c4_b06e_4bc1_bd8c_6297c8669100"
      unitRef="pure">-0.0727</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2023_S000003866Member_C000010832Member"
      decimals="4"
      id="h_b955f5d1_f93d_4bac_894e_ac4e043b54f8"
      unitRef="pure">0.1325</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2022_S000003866Member_C000010832Member"
      decimals="4"
      id="h_e5a4803a_2b6a_49ae_b0dd_f81c6ec2ff65"
      unitRef="pure">-0.1573</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2017_S000003866Member_C000010832Member"
      decimals="4"
      id="h_f684e29d_832d_4aff_b21f_62a244d5369b"
      unitRef="pure">0.1405</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2019_S000003870Member_C000010836Member"
      decimals="4"
      id="h_02bb004a_cd53_4634_a428_6468bdfa0c00"
      unitRef="pure">0.0178</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2021_S000003870Member_C000010836Member"
      decimals="4"
      id="h_090380e0_8a33_459c_a5d3_66b3e0eb3406"
      unitRef="pure">0.0001</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2016_S000003870Member_C000010836Member"
      decimals="4"
      id="h_25b15859_22c5_4938_8de7_f2c9228346c9"
      unitRef="pure">0.0000</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2022_S000003870Member_C000010836Member"
      decimals="4"
      id="h_2e78e87e_394a_425f_a246_27bf2601dafd"
      unitRef="pure">0.0126</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2017_S000003870Member_C000010836Member"
      decimals="4"
      id="h_65bfb7ae_f331_417d_ab63_5b53ff26a75e"
      unitRef="pure">0.0045</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2020_S000003870Member_C000010836Member"
      decimals="4"
      id="h_6e10234a_7867_42b0_8bd7_63929ee7d248"
      unitRef="pure">0.0026</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2024_S000003870Member_C000010836Member"
      decimals="4"
      id="h_807b93bd_e246_475c_bbb4_5236062df19d"
      unitRef="pure">0.0482</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2018_S000003870Member_C000010836Member"
      decimals="4"
      id="h_a83e242d_a30f_4b8e_87d6_2d1993f7485e"
      unitRef="pure">0.0141</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2023_S000003870Member_C000010836Member"
      decimals="4"
      id="h_b9005c05_a2fd_4eeb_9946_91baea9574fd"
      unitRef="pure">0.0465</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="FY2025_S000003870Member_C000010836Member"
      decimals="4"
      id="h_c9529925_55f2_4ebc_abb9_034129cef50d"
      unitRef="pure">0.0390</oef:AnnlRtrPct>
    <dei:EntityInvCompanyType
      contextRef="DefaultContext"
      id="h_01_4413b1f2_194c_4d12_a47b_7db9d9896f1b">N-1A</dei:EntityInvCompanyType>
    <dei:EntityRegistrantName
      contextRef="DefaultContext"
      id="t_4_d9277cbf_7708_395f_b6de_da9ca62f7f29">BlackRock Series Fund, Inc.</dei:EntityRegistrantName>
    <oef:ProspectusDate
      contextRef="DefaultContext"
      id="h_03_9e753d19_4f8f_40a9_aefe_3632ddc59e00">2026-05-01</oef:ProspectusDate>
    <oef:RiskReturnHeading
      contextRef="S000003864Member"
      id="t_1_db0ff0b2_46d5_4918_af75_abfc6f194861"> Fund Overview  Key Facts About BlackRock Advantage Large Cap Core Portfolio </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="S000003864Member"
      id="t_2_f34dd48d_343c_4d65_9d1c_ebd5634cd8f1"> Investment Objective  </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="S000003864Member"
      id="t_3_e4a97fc4_08c6_45d9_9885_b6d800c0c820"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The investment objective of BlackRock Advantage Large Cap Core Portfolio (the &#x201c;Advantage Large Cap Core Portfolio&#x201d; or the &#x201c;Fund&#x201d;), a series of BlackRock Series Fund, Inc. (the &#x201c;Corporation&#x201d;), is to seek long-term capital appreciation.&lt;/div&gt; </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="S000003864Member"
      id="t_4_89064194_3f75_4b93_b4f0_adea47c5d314"> Fees and Expenses of the Fund  </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="S000003864Member"
      id="t_5_2ee783a3_8ecf_48e8_906b_3542772841f7"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. &lt;span style="font-weight: bold;"&gt;The table and example below do not include separate account fees and expenses, and expenses would be higher if these fees and expenses were included.&lt;/span&gt; Please refer to your variable annuity or insurance contract (the &#x201c;Contract&#x201d;) prospectus for information on the separate account fees and expenses associated with your Contract.&lt;/div&gt; </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="S000003864Member"
      id="t_6_4280ce36_afde_4f97_a0e1_97fbe55cfc23"> Shareholder Fees (fees paid directly from your investment)  The Fund is not subject to any Shareholder Fees. </oef:ShareholderFeesCaption>
    <oef:OperatingExpensesCaption
      contextRef="S000003864Member"
      id="t_7_4415782f_6b1b_4212_9c9c_911a6d10f7e7">Annual Fund Operating Expenses(expenses that you pay each year as a percentage of the value of your investment)</oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="S000003864Member_C000010830Member"
      decimals="4"
      id="h_1_1ee59a5d_a773_4fd9_a39a_cbfb9c1f3b29"
      unitRef="pure">0.0037</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="S000003864Member_C000010830Member"
      decimals="4"
      id="h_2_bbd69e14_1fdd_495f_85c6_a8e958c2075c"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="S000003864Member_C000010830Member"
      decimals="4"
      id="h_3_a0515855_9c62_4b10_ae0a_263fe9eb5924"
      unitRef="pure">0.0020</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="S000003864Member_C000010830Member"
      decimals="4"
      id="h_4_365bb5f0_aaf9_4431_a20b_da6595c35f4d"
      unitRef="pure">0.0057</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="S000003864Member_C000010830Member"
      decimals="4"
      id="h_5_9fbb1d47_6c58_4e67_a078_e952ee74fd17"
      unitRef="pure">-0.0009</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="S000003864Member_C000010830Member"
      decimals="4"
      id="h_6_a5b40651_75cf_4a2c_bdf2_4006345e87b6"
      unitRef="pure">0.0048</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="S000003864Member"
      id="t_19_6a25dd32_d0b8_3150_d773_e888858b59e5">June 30, 2027</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpenseExampleHeading
      contextRef="S000003864Member"
      id="t_8_92ff5e93_d97b_4975_aad7_041e12329990"> Example: </oef:ExpenseExampleHeading>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="S000003864Member"
      id="t_9_f88601f2_1414_465a_a01e_fdb1d6c55d71"> &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund&#x2019;s operating expenses remain the same. The Example does not reflect charges imposed by the Contract. See the Contract prospectus for information on such charges. Although your actual costs may be higher or lower, based on these assumptions your costs would be:&lt;/div&gt; </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="S000003864Member_C000010830Member"
      decimals="INF"
      id="h_7_bd730329_1fb7_4128_9632_560b49cb580f"
      unitRef="USD">49</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="S000003864Member_C000010830Member"
      decimals="INF"
      id="h_8_96fa376c_1664_4c52_9e77_b68beb8e1722"
      unitRef="USD">174</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="S000003864Member_C000010830Member"
      decimals="INF"
      id="h_9_d866c102_e3da_455d_ae97_04a449752d1a"
      unitRef="USD">309</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="S000003864Member_C000010830Member"
      decimals="INF"
      id="h_10_9f71159d_da93_4f0d_9ac0_e7f7a34f30b5"
      unitRef="USD">705</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="S000003864Member"
      id="t_10_34e76984_81ed_4b7f_a68e_5ef79da94416"> Portfolio Turnover: </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="S000003864Member"
      id="t_11_25816211_e274_4025_9566_406cf0fbdf78"> &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund pays transaction costs, such as commissions, when it buys and sells securities (or &#x201c;turns over&#x201d; its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund&#x2019;s performance. During the most recent fiscal year, the Fund&#x2019;s portfolio turnover rate was 114% of the average value of its portfolio.&lt;/div&gt; </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="S000003864Member"
      decimals="4"
      id="h_11_adf683b6_301f_42f5_bc4f_d463faef4d07"
      unitRef="pure">1.14</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="S000003864Member"
      id="t_12_49f1ad6f_60cc_432b_add1_86c94f166bc7"> Principal Investment Strategies of the Fund  </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="S000003864Member"
      id="t_13_6c111166_e92b_43e6_a1e4_472d18921dd2"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;Under normal circumstances, the Fund seeks to invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in large cap equity securities and derivatives that have similar economic&lt;/div&gt;  &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;characteristics to such securities. Investments in derivatives are counted toward the Fund&#x2019;s 80% policy to the extent that they provide investment exposure to the securities included within that policy or to one or more market risk factors associated with such securities. For purposes of the Fund&#x2019;s 80% policy, large cap equity securities are equity securities that at the time of purchase have a market capitalization within the range of companies included in the Russell 1000&lt;sup style="font-size: 75%; vertical-align: top;"&gt;&#xae;&lt;/sup&gt; Index (the &#x201c;Russell 1000 Index&#x201d;). The Fund primarily intends to invest in equity securities, which include common stock and preferred stock, or other financial instruments that are components of, or have characteristics similar to, the securities included in the Russell 1000 Index. The Russell 1000 Index is a capitalization-weighted index of equity securities from a broad range of industries chosen for market size, liquidity and industry group representation. The Fund primarily seeks to buy common stock and may also invest in preferred stock and convertible securities. From time to time, the Fund may invest in shares of companies through &#x201c;new issues&#x201d; or initial public offerings (&#x201c;IPOs&#x201d;).&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund may use derivatives, including options, futures, swaps (including, but not limited to, total return swaps, some of which may be referred to as contracts for difference) and forward contracts, both to seek to increase the return of the Fund and to hedge (or protect) the value of its assets against adverse movements in currency exchange rates, interest rates and movements in the securities markets. In order to manage cash flows into or out of the Fund effectively, the Fund may buy and sell financial futures contracts or options on such contracts. Derivatives are financial instruments whose value is derived from another security, a currency or an index, including but not limited to the Russell 1000 Index. The use of options, futures, swaps and forward contracts can be effective in protecting or enhancing the value of the Fund&#x2019;s assets.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund may seek to provide exposure to the investment returns of real assets that trade in the commodity markets through investment in commodity-linked derivative instruments and investment vehicles such as exchange-traded funds that invest exclusively in commodities and are designed to provide this exposure without direct investment in physical commodities.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund seeks to pursue its investment objective by investing in large cap securities in a disciplined manner, by using proprietary return forecast models that incorporate quantitative analysis. These forecast models are designed to identify aspects of mispricing across stocks which the Fund can seek to capture by over- and under-weighting particular equities while seeking to control incremental risk. BlackRock then constructs and rebalances the portfolio by integrating its investment insights with the model-based optimization process.&lt;/div&gt; </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_RiskLoseMoneyMember"
      id="t_25_32e4d18b_13a0_ba96_8498_c1856b1d88d7">&#160;You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_EquitySecuritiesRiskMember"
      id="t_26_0f67098c_b9fd_3f81_9187_ce1dd50a75ce"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Equity Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Stock markets are volatile. The price of equity securities fluctuates based on changes in a company&#x2019;s financial condition and overall market and economic conditions.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_InvestmentStyleRiskMember"
      id="t_27_3665bd72_c918_006d_243e_0f4c9d6e9a79"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Investment Style Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Under certain market conditions, growth investments have performed better during the later stages of economic expansion and value investments have performed better during periods of economic recovery. Therefore, these investment styles may over time go in and out of favor. At times when the investment style used by the Fund is out of favor, the Fund may underperform other equity funds that use different investment styles.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_ModelRiskMember"
      id="t_28_eec0fb54_0c49_7e70_00f4_4415ffef28cd"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Model Risk&lt;/span&gt;&lt;/span&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt; &lt;/span&gt;&lt;/span&gt;&#x2014; The Fund seeks to pursue its investment objective by using proprietary models that incorporate quantitative analysis. Investments selected using these models may perform differently than as forecasted due to the factors incorporated into the models and the weighting of each factor, changes from historical trends, and issues in the construction and implementation of the models (including, but not limited to, software issues, issues related to the use of artificial intelligence and machine learning (&#x201c;AI&#x201d;), and other technological issues). There is no guarantee that BlackRock&#x2019;s use of these models will result in effective investment decisions for the Fund.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;The information and data used in the models may be supplied by third parties. Inaccurate or incomplete data may limit the effectiveness of the models. In addition, some of the data that BlackRock uses may be historical data, which may not accurately predict future market movement. There is a risk that the models will not be successful in selecting investments or in determining the weighting of investment positions that will enable the Fund to achieve its investment objective.&lt;/div&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_RiskOfInvestingInTheUnitedStatesMember"
      id="t_29_4fe1e262_0cee_d42a_8e7a_16342d83d1c3"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Risk of Investing in the United States&lt;/span&gt;&lt;/span&gt; &#x2014; Certain changes in the U.S. economy, such as when the U.S. economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_CommoditiesRelatedInvestmentsRiskMember"
      id="t_30_89c169fa_e5d3_4a07_d263_4a34b876bea4"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Commodities Related Investments Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Exposure to the commodities markets may subject the Fund to greater volatility than investments in traditional securities. The value of commodity-linked derivative investments may be affected by changes in overall market movements, commodity index volatility, changes in inflation, interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, embargoes, tariffs and international economic, political and regulatory developments.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_ConvertibleSecuritiesRiskMember"
      id="t_31_1ecff34e_1c47_0bc9_4181_acaad21bea65"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Convertible Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The market value of a convertible security performs like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest, principal or dividends when due, and their market value may change based on changes in the issuer&#x2019;s credit rating or the market&#x2019;s perception of the issuer&#x2019;s creditworthiness. Since it derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock, including the potential for increased volatility in the price of the convertible security.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_DerivativesRisksMember"
      id="t_32_238a63b6_b494_ab69_2f35_05501c6e443c"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Derivatives Risk &lt;/span&gt;&lt;/span&gt;&#x2014; The Fund&#x2019;s use of derivatives may increase its costs, reduce the Fund&#x2019;s returns and/or increase volatility. Derivatives involve significant risks, including:&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Leverage Risk &lt;/span&gt;&#x2014; The Fund&#x2019;s use of derivatives can magnify the Fund&#x2019;s gains and losses. Relatively small market movements may result in large changes in the value of a derivatives position and can result in losses that greatly exceed the amount originally invested.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Market Risk&lt;/span&gt; &#x2014; Some derivatives are more sensitive to interest rate changes and market price fluctuations than other securities. The Fund could also suffer losses related to its derivatives positions as a result of unanticipated market movements, which losses are potentially unlimited. Finally, BlackRock may not be able to predict correctly the direction of securities prices, interest rates and other economic factors, which could cause the Fund&#x2019;s derivatives positions to lose value.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Counterparty Risk&lt;/span&gt; &#x2014; Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will be unable or unwilling to fulfill its contractual obligation, and the related risks of having concentrated exposure to such a counterparty.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Illiquidity Risk&lt;/span&gt; &#x2014; The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Operational Risk&lt;/span&gt; &#x2014; The use of derivatives includes the risk of potential operational issues, including documentation issues, settlement issues, systems failures, inadequate controls and human error.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Legal Risk&lt;/span&gt; &#x2014; The risk of insufficient documentation, insufficient capacity or authority of counterparty, or legality or enforceability of a contract.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Volatility and Correlation Risk&lt;/span&gt; &#x2014; Volatility is defined as the characteristic of a security, an index or a market to fluctuate significantly in price within a short time period. A risk of the Fund&#x2019;s use of derivatives is that the fluctuations in their values may not correlate with the overall securities markets.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Valuation Risk &lt;/span&gt;&#x2014; Valuation for derivatives may not be readily available in the market. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Hedging Risk&lt;/span&gt; &#x2014; Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Fund&#x2019;s hedging transactions will be effective. The use of hedging may result in certain adverse tax consequences.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Tax Risk &lt;/span&gt;&#x2014; Certain aspects of the tax treatment of derivative instruments, including swap agreements and commodity-linked derivative instruments, are currently unclear and may be affected by changes in legislation, regulations or other legally binding authority. Such treatment may be less favorable than that given to a direct investment in an underlying asset and may adversely affect the timing, character and amount of income the Fund realizes from its investments.&lt;/div&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_HighPortfolioTurnoverRiskMember"
      id="t_33_44c769f5_8e17_7f58_41e1_e3517f572d4e"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;High Portfolio Turnover Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The Fund may engage in active and frequent trading of its portfolio securities. High portfolio turnover (more than 100%) may result in increased transaction costs to the Fund, including brokerage commissions, dealer mark&#x2011;ups and other transaction costs on the sale of the securities and on reinvestment in other securities. The sale of Fund portfolio securities may result in the realization and/or distribution to shareholders of higher capital gains or losses as compared to a fund with less active trading policies. These effects of higher than normal portfolio turnover may adversely affect Fund performance.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_LargeCapitalizationCompaniesRiskMember"
      id="t_34_61689b5f_a666_a3d9_5ab8_f0330364c5bb"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Large-Capitalization Companies Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Large-capitalization companies may be less able than smaller-capitalization companies to adapt to changing market conditions and competitive challenges. Large-capitalization companies may be more mature and subject to more limited growth potential compared with smaller-capitalization companies. The performance of large-capitalization companies could trail the overall performance of the broader securities markets.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_LeverageRiskMember"
      id="t_35_e7472cc8_a2e7_b3b0_b223_d8f2cba94672"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Leverage Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Some transactions may give rise to a form of economic leverage. These transactions may include, among others, derivatives, and may expose the Fund to greater risk and increase its costs. The use of leverage may cause the Fund to liquidate portfolio positions when it may not be advantageous to do so to satisfy its obligations or to meet the applicable requirements of the Investment Company Act of 1940, as amended, (the &#x201c;Investment Company Act&#x201d;) and the rules thereunder. Increases and decreases in the value of the Fund&#x2019;s portfolio will be magnified when the Fund uses leverage.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_MarketRiskAndSelectionRiskMember"
      id="t_36_1375c4b4_ac10_b102_daa0_846a4bb713c1"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Market Risk and Selection Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a security or other asset may decline due to changes in general market conditions, economic trends or events that are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its investments. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. The Fund seeks to pursue its investment objective by using proprietary models that incorporate quantitative analysis and is subject to &#x201c;Model Risk&#x201d; as described above. This means you may lose money.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_NewIssuesRiskMember"
      id="t_37_6b1751f2_728b_f9ca_f71a_688e5682c3df"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;&#x201c;New Issues&#x201d; Risk&lt;/span&gt;&lt;/span&gt; &#x2014; &#x201c;New issues&#x201d; are IPOs of equity securities. Securities issued in IPOs have no trading history, and information about the companies may be available for very limited periods. In addition, the prices of securities sold in IPOs may be highly volatile or may decline shortly after the IPO.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_OperationalAndTechnologyRisksMember"
      id="t_38_c8f9fcdc_328f_029d_b587_49a1253d39a3"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Operational and Technology Risks&lt;/span&gt;&lt;/span&gt; &#x2014; The Fund is directly and indirectly susceptible to operational and technology risks, including those related to human errors, processing errors, communication errors, systems failures, cybersecurity incidents, and the use of AI, which may result in losses for the Fund and its shareholders or may impair the Fund&#x2019;s operations. While the Fund&#x2019;s service providers are required to have appropriate operational, information security and cybersecurity risk management policies and procedures, their methods of risk management may differ from those of the Fund. Operational and technology risks for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and may cause the Fund&#x2019;s investments in such issuers to lose value.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003864Member_PreferredSecuritiesRiskMember"
      id="t_39_b3457421_0ce7_0531_f67f_815cce6451b5"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Preferred Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Preferred securities may pay fixed or adjustable rates of return. Preferred securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company&#x2019;s preferred securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company&#x2019;s financial condition or prospects. Preferred securities of smaller companies may be more vulnerable to adverse developments than preferred securities of larger companies.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="S000003864Member"
      id="t_15_d920c3c6_90b5_4b37_9d12_2b745fa859f5"> Performance Information  </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="S000003864Member"
      id="t_44_d30bb6ab_4d7b_3db9_dfe5_10f9aba9a0a9"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The information shows you how the Fund&#x2019;s performance has varied year by year and provides some indication of the risks of investing in the Fund. The Fund&#x2019;s returns prior to June 12, 2017 as reflected in the bar chart and the table are the returns of the Fund when it followed different investment strategies under the name &#x201c;BlackRock Large Cap Core Portfolio.&#x201d; The table compares the Fund&#x2019;s performance to that of the Russell 1000&#xae; Index. To the extent that dividends and distributions have been paid by the Fund, the performance information for the Fund in the chart and table assumes reinvestment of the dividends and distributions. As with all such investments, past performance is not an indication of future results. The bar chart and table do not reflect separate account fees and expenses. If they did, returns would be less than those shown. If the Fund&#x2019;s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund&#x2019;s returns would have been lower.&lt;/div&gt; </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="S000003864Member"
      id="t_45_c3a54ad9_7b45_619d_4a56_371992c20839">The information shows you how the Fund&#x2019;s performance has varied year by year and provides some indication of the risks of investing in the Fund.</oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="S000003864Member"
      id="t_46_d9cc356f_597b_40e5_28f6_df6cd17aed05">As with all such investments, past performance is not an indication of future results.</oef:PerformancePastDoesNotIndicateFuture>
    <oef:BarChartDoesNotReflectSalesLoads
      contextRef="S000003864Member"
      id="t_47_b8aa7d9b_d5f7_9661_32be_da1c9bf0d0ae">The bar chart and table do not reflect separate account fees and expenses. If they did, returns would be less than those shown.</oef:BarChartDoesNotReflectSalesLoads>
    <oef:BarChartHeading
      contextRef="S000003864Member"
      id="t_17_6154377e_95ef_450a_a6f6_b852ec3f5a67"> ANNUAL TOTAL RETURNS  BlackRock Advantage Large Cap Core Portfolio  As of 12/31 </oef:BarChartHeading>
    <oef:BarChartClosingTextBlock
      contextRef="S000003864Member"
      id="t_23_0d635c6c_b842_0286_7201_1cae59aba42a"> &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;During the ten&#x2011;year period shown in the bar chart, the highest return for a quarter was 21.89% (quarter ended June&#160;30, 2020) and the lowest return for a quarter was &#x2013;19.71% (quarter ended March 31, 2020).&lt;/div&gt; </oef:BarChartClosingTextBlock>
    <oef:HighestQuarterlyReturnLabel
      contextRef="S000003864Member_C000010830Member"
      id="t_40_e020623b_4a21_989a_9c66_702cc0bb6ba9">highest return</oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="S000003864Member_C000010830Member"
      decimals="4"
      id="h_18_a65de543_f2dc_d4c5_ee01_18f1cd88e618"
      unitRef="pure">0.2189</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="S000003864Member_C000010830Member"
      id="t_41_60de349d_aa15_40db_9e51_3fadd42da606">2020-06-30</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="S000003864Member_C000010830Member"
      id="t_42_b2028472_0923_ccf2_cf7b_497c16dec544">lowest return</oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="S000003864Member_C000010830Member"
      decimals="4"
      id="h_19_123dfd96_2c17_5b86_b18c_32685770088e"
      unitRef="pure">-0.1971</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="S000003864Member_C000010830Member"
      id="t_43_4bcbe6f7_1efa_e6f9_fa8a_1fca236eae07">2020-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:PerformanceTableHeading
      contextRef="S000003864Member"
      id="t_24_f6365811_812a_7ec0_027a_82d02788af9e">For the periods ended 12/31/25Average Annual Total Returns</oef:PerformanceTableHeading>
    <oef:AvgAnnlRtrPct
      contextRef="FY2025_C000010830Member"
      decimals="4"
      id="h_12_66001724_3ae3_4db7_8621_adb0a3b3b045"
      unitRef="pure">0.2020</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FiveY2025_C000010830Member"
      decimals="4"
      id="h_13_2a320e00_d4a4_49ae_b1aa_6fda994f606f"
      unitRef="pure">0.1427</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="TenY2025_C000010830Member"
      decimals="4"
      id="h_14_e72e35e0_91a1_4b28_90e6_1c07a80e3213"
      unitRef="pure">0.1450</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FY2025_Russell1000IndexMember"
      decimals="4"
      id="h_15_1314e9c6_4260_469e_80c4_ac20baa802c0"
      unitRef="pure">0.1737</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FiveY2025_Russell1000IndexMember"
      decimals="4"
      id="h_16_973350df_a22f_46f7_ba90_91010d51ac02"
      unitRef="pure">0.1359</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="TenY2025_Russell1000IndexMember"
      decimals="4"
      id="h_17_5d24ca38_c043_43d8_99c3_ed13392ae823"
      unitRef="pure">0.1459</oef:AvgAnnlRtrPct>
    <oef:RiskReturnHeading
      contextRef="S000003863Member"
      id="t_19_f922ba87_34d8_4e76_b4d9_359f745f67ee"> Fund Overview  Key Facts About BlackRock Balanced Portfolio </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="S000003863Member"
      id="t_20_ea29b569_96d1_4d55_8079_2827e93bdfd4"> Investment Objective  </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="S000003863Member"
      id="t_21_4e773b3e_c3d3_4ca9_a25e_d1073dd1cdf9"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The investment objective of BlackRock Balanced Portfolio (the &#x201c;Balanced Portfolio&#x201d; or the &#x201c;Fund&#x201d;) (formerly known as BlackRock Sustainable Balanced Portfolio), a series of BlackRock Series Fund, Inc. (the &#x201c;Corporation&#x201d;), is to seek high total investment return.&lt;/div&gt; </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="S000003863Member"
      id="t_22_4624a6c3_e13f_4af4_bf54_48d8363583bf"> Fees and Expenses of the Fund  </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="S000003863Member"
      id="t_23_8bc365d0_d326_4713_ab03_854e56d2c0d7"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. &lt;span style="font-weight: bold;"&gt;The table and example below do not include separate account fees and expenses, and expenses would be higher if these fees and expenses were included.&lt;/span&gt; Please refer to your variable annuity or insurance contract (the &#x201c;Contract&#x201d;) prospectus for information on the separate account fees and expenses associated with your Contract.&lt;/div&gt; </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="S000003863Member"
      id="t_24_977553aa_cb81_414f_be55_45c3c76fe65c"> Shareholder Fees (fees paid directly from your investment)  The Fund is not subject to any Shareholder Fees. </oef:ShareholderFeesCaption>
    <oef:OperatingExpensesCaption
      contextRef="S000003863Member"
      id="t_25_bcabec8c_3278_4f57_81c4_4d4e65e69cd8"> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="S000003863Member_C000010829Member"
      decimals="4"
      id="h_18_70a8bf2e_db88_4f37_acb5_6dce8d2d2b34"
      unitRef="pure">0.0037</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="S000003863Member_C000010829Member"
      decimals="4"
      id="h_19_9107bb96_2078_44f1_92f3_94f565a38ea0"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="S000003863Member_C000010829Member"
      decimals="4"
      id="h_20_a6ada589_03df_4960_91e5_6d480c17fc12"
      unitRef="pure">0.0022</oef:OtherExpensesOverAssets>
    <oef:Component1OtherExpensesOverAssets
      contextRef="S000003863Member_C000010829Member"
      decimals="4"
      id="h_21_a75e972b_45ee_4c0e_8e62_b7f6f72f8cb6"
      unitRef="pure">0.0001</oef:Component1OtherExpensesOverAssets>
    <oef:Component2OtherExpensesOverAssets
      contextRef="S000003863Member_C000010829Member"
      decimals="4"
      id="h_22_24368dc1_70bf_4734_a413_7966f26e8a6e"
      unitRef="pure">0.0021</oef:Component2OtherExpensesOverAssets>
    <oef:AcquiredFundFeesAndExpensesOverAssets
      contextRef="S000003863Member_C000010829Member"
      decimals="4"
      id="h_23_c4f263d6_7a98_4905_89e0_a5d97aa16ce2"
      unitRef="pure">0.0001</oef:AcquiredFundFeesAndExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="S000003863Member_C000010829Member"
      decimals="4"
      id="h_24_0fe2f2c3_694d_4414_a5b0_b6502c681cf9"
      unitRef="pure">0.0060</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="S000003863Member_C000010829Member"
      decimals="4"
      id="h_25_06e7876c_c1e7_4dbd_86b8_3d2e02e7b871"
      unitRef="pure">-0.0010</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="S000003863Member_C000010829Member"
      decimals="4"
      id="h_26_af7173b2_fd9f_4734_9798_397f57a71666"
      unitRef="pure">0.0050</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="S000003863Member"
      id="t_38_ab32f2bf_cc75_6e4a_f9e7_cbb7eb39030f">June&#160;30, 2027</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpensesNotCorrelatedToRatioDueToAcquiredFundFees
      contextRef="S000003863Member"
      id="t_39_94db1ff7_1a76_f659_74fe_0964323cb43b">The Total Annual Fund Operating Expenses does not correlate to the ratio of expenses to average net assets given in the Fund&#x2019;s most recent Annual Financial Statements and Additional Information, which does not include Acquired Fund Fees and Expenses.</oef:ExpensesNotCorrelatedToRatioDueToAcquiredFundFees>
    <oef:ExpenseExampleHeading
      contextRef="S000003863Member"
      id="t_26_980147fb_fff8_41c1_b741_6900b7405302"> Example: </oef:ExpenseExampleHeading>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="S000003863Member"
      id="t_27_0d48ed0d_c841_4e2e_a147_5563370e245c"> &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund&#x2019;s operating expenses remain the same. The Example does not reflect charges imposed by the Contract. See the Contract prospectus for information on such charges. Although your actual costs may be higher or lower, based on these assumptions your costs would be:&lt;/div&gt; </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="S000003863Member_C000010829Member"
      decimals="INF"
      id="h_27_32ddea15_65e1_49f2_8ce6_3f482e1a90c4"
      unitRef="USD">51</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="S000003863Member_C000010829Member"
      decimals="INF"
      id="h_28_781897f4_8e8e_45c5_95c1_09858107cd35"
      unitRef="USD">182</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="S000003863Member_C000010829Member"
      decimals="INF"
      id="h_29_293410ac_2f73_4037_8873_61914dbaec87"
      unitRef="USD">325</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="S000003863Member_C000010829Member"
      decimals="INF"
      id="h_30_f953ba89_abfa_4cca_8541_fca1f85fd28f"
      unitRef="USD">740</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="S000003863Member"
      id="t_28_59f8585a_2e99_4d3c_8217_73a8f671525c"> Portfolio Turnover: </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="S000003863Member"
      id="t_29_4e02c817_8bd8_42cb_a510_fd646270406e"> &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund pays transaction costs, such as commissions, when it buys and sells securities (or &#x201c;turns over&#x201d; its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when shares are&lt;/div&gt;  &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund&#x2019;s performance. During the most recent fiscal year, the Fund&#x2019;s portfolio turnover rate was 110% of the average value of its portfolio.&lt;/div&gt; </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="S000003863Member"
      decimals="4"
      id="h_31_14aea6a6_7161_4e3b_b188_65b9dfe92e59"
      unitRef="pure">1.10</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="S000003863Member"
      id="t_30_d8a3e91f_bfd0_41fc_9e6c_4995f018ed42"> Principal Investment Strategies of the Fund  </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="S000003863Member"
      id="t_31_cf788507_5efa_4138_aa87_74861a946626"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund invests in a combination of equity securities, fixed-income securities and derivatives. The proportion the Fund invests in each category at any given time depends on Fund management&#x2019;s view of how attractive that category appears relative to the others. The Fund intends to invest at least 25% of its assets in equity securities and at least 25% of its assets in senior fixed income securities, such as U.S. government debt securities, corporate debt securities, and mortgage-backed and asset-backed securities.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;With respect to the Fund&#x2019;s equity investments, the Fund primarily intends to invest in equity securities or other financial instruments that are components of, or have characteristics similar to, the securities included in the MSCI All Country World Index (the &#x201c;ACWI&#x201d;). The ACWI is a capitalization-weighted index from a broad range of industries chosen for market size, liquidity and industry group representation. In selecting equity investments, the Fund primarily uses proprietary return forecast models that incorporate quantitative analysis. Equity securities include common stock and preferred stock. The Fund primarily seeks to buy common stock and may also invest in preferred stock. From time to time, the Fund may invest in shares of companies through &#x201c;new issues&#x201d; or initial public offerings (&#x201c;IPOs&#x201d;). The Fund may also purchase convertible securities. The Fund may invest in securities of both U.S. or non&#x2011;U.S. issuers without limit, which can be U.S. dollar based or non&#x2011;U.S. dollar based and may be currency hedged or unhedged. The Fund may invest in securities of companies of any market capitalization.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;With respect to the Fund&#x2019;s fixed-income investments, the Fund will invest primarily using model-based asset allocation and security selection models. The Fund may invest in obligations issued or guaranteed by the U.S. Government, its agencies or instrumentalities; mortgage-backed securities issued or guaranteed by the U.S. Government or its agencies or instrumentalities, including U.S. agency mortgage pass-through securities; commercial mortgage-backed securities; mortgage to&#x2011;be&#x2011;announced (&#x201c;TBA&#x201d;) securities; debt obligations of U.S. issuers, including corporate bonds; municipal securities; asset-backed securities; and U.S.-registered dollar-denominated debt obligations of foreign issuers. The Fund may invest in bonds issued by companies located in countries other than the United States, including companies in emerging markets. These securities may have all types of interest rate payment and reset terms, including fixed rate, adjustable rate, floating rate, zero coupon, contingent, deferred, payment in kind and auction rate features. The Fund seeks to invest a substantial portion of its assets in U.S.-registered, dollar-denominated bonds. The Fund may invest up to 10% of its assets in securities rated below investment grade (&#x201c;high&#160;yield&#x201d; or &#x201c;junk&#x201d; bonds). The Fund may invest in bonds of any maturity or duration.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund may invest a significant portion of its fixed income holdings in U.S. agency mortgage pass-through securities, which are securities issued by entities such as the Government National Mortgage Association (&#x201c;GNMA&#x201d;) and the Federal National Mortgage Association that are backed by pools of mortgages. Most transactions in mortgage pass-through securities occur through standardized contracts for future delivery in which the exact mortgage-backed securities to be delivered are not specified until a few days prior to settlement. The Fund expects to enter into such contracts on a regular basis.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund may use derivatives, including options, futures, swaps (including, but not limited to, total return swaps) forward contracts and various other instruments, both to seek to increase the return of the Fund and to hedge (or protect) the value of its assets against adverse movements in currency exchange rates, interest rates and movements in the securities markets. The Fund may also invest in indexed and inverse securities.&lt;/div&gt; </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_RiskLoseMoneyMember"
      id="t_46_4374e737_97a9_1b91_141d_7b15eab6889e">You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_EquitySecuritiesRiskMember"
      id="t_47_705636a8_24b2_c28a_07e3_4a2f216b17b7"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Equity Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Stock markets are volatile. The price of equity securities fluctuates based on changes in a company&#x2019;s financial condition and overall market and economic conditions.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_DebtSecuritiesRiskMember"
      id="t_48_f1fe7fae_15d7_9657_0ff9_6287c95f8f3b"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Debt Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Debt securities, such as bonds, involve risks, such as credit risk, interest rate risk, extension risk, and prepayment risk, each of which are described in further detail below:&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Credit Risk&lt;/span&gt; &#x2014; Credit risk refers to the possibility that the issuer of a debt security (i.e., the borrower) will not be able to make payments of interest and principal when due. Changes in an issuer&#x2019;s credit rating or the market&#x2019;s perception of an issuer&#x2019;s creditworthiness may also affect the value of the Fund&#x2019;s investment in that issuer. The degree of credit risk depends on both the financial condition of the issuer and the terms of the obligation.&lt;/div&gt;  &lt;div style="margin-top: 0pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Interest Rate Risk&lt;/span&gt; &#x2014; The market value of bonds and other fixed-income securities changes in response to interest rate changes and other factors. Interest rate risk is the risk that prices of bonds and other fixed-income securities will increase as interest rates fall and decrease as interest rates rise.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;The Fund may be subject to a greater risk of rising interest rates during a period of historically low interest rates. For example, if interest rates increase by 1%, assuming a current portfolio duration of ten years, and all other factors being equal, the value of the Fund&#x2019;s investments would be expected to decrease by 10%. (Duration is a measure of the price sensitivity of a debt security or portfolio of debt securities to relative changes in interest rates.) The magnitude of these fluctuations in the market price of bonds and other fixed-income securities is generally greater for those securities with longer maturities. Fluctuations in the market price of the Fund&#x2019;s investments will not affect interest income derived from instruments already owned by the Fund, but will be reflected in the Fund&#x2019;s net asset value. The Fund may lose money if short-term or long-term interest rates rise sharply in a manner not anticipated by Fund management.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;To the extent the Fund invests in debt securities that may be prepaid at the option of the obligor (such as mortgage-backed securities), the sensitivity of such securities to changes in interest rates may increase (to the detriment of the Fund) when interest rates rise. Moreover, because rates on certain floating rate debt securities typically reset only periodically, changes in prevailing interest rates (and particularly sudden and significant changes) can be expected to cause some fluctuations in the net asset value of the Fund to the extent that it invests in floating rate debt securities.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;These basic principles of bond prices also apply to U.S. Government securities. A security backed by the &#x201c;full faith and credit&#x201d; of the U.S. Government is guaranteed only as to its stated interest rate and face value at maturity, not its current market price. Just like other fixed-income securities, government-guaranteed securities will fluctuate in value when interest rates change.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;A general rise in interest rates has the potential to cause investors to move out of fixed-income securities on a large scale, which may increase redemptions from funds that hold large amounts of fixed-income securities. Heavy redemptions could cause the Fund to sell assets at inopportune times or at a loss or depressed value and could hurt the Fund&#x2019;s performance.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Extension Risk&lt;/span&gt; &#x2014; When interest rates rise, certain obligations will be paid off by the obligor more slowly than anticipated, causing the value of these obligations to fall.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Prepayment Risk&lt;/span&gt; &#x2014; When interest rates fall, certain obligations will be paid off by the obligor more quickly than originally anticipated, and the Fund may have to invest the proceeds in securities with lower yields.&lt;/div&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_ForeignSecuritiesRiskMember"
      id="t_49_be45e951_45fb_b10e_744f_33bf3e0b71ee"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Foreign Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Foreign investments often involve special risks not present in U.S. investments that can increase the chances that the Fund will lose money. These risks include:&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;The Fund generally holds its foreign securities and cash in foreign banks and securities depositories, which may be recently organized or new to the foreign custody business and may be subject to only limited or no regulatory oversight.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;Changes in foreign currency exchange rates can affect the value of the Fund&#x2019;s portfolio.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;The economies of certain foreign markets may not compare favorably with the economy of the United States with respect to such issues as growth of gross national product, reinvestment of capital, resources and balance of payments position.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;The governments of certain countries, or the U.S. Government with respect to certain countries, may prohibit or impose substantial restrictions through capital controls and/or sanctions on foreign investments in the capital markets or certain industries in those countries, which may prohibit or restrict the ability to own or transfer currency, securities, derivatives or other assets.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to the same extent as does the United States and may not have laws to protect investors that are comparable to U.S. securities laws.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;Settlement and clearance procedures in certain foreign markets may result in delays in payment for or delivery of securities not typically associated with settlement and clearance of U.S. investments.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;The Fund&#x2019;s claims to recover foreign withholding taxes may not be successful, and if the likelihood of recovery of foreign withholding taxes materially decreases, due to, for example, a change in tax regulation or approach in the foreign country, accruals in the Fund&#x2019;s net asset value for such refunds may be written down partially or in full, which will adversely affect the Fund&#x2019;s net asset value.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_ConvertibleSecuritiesRiskMember"
      id="t_50_7fae3f21_7e8f_02f9_7984_e42e3b807033"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Convertible Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The market value of a convertible security performs like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest, principal or dividends when due, and their market value may change based on changes in the issuer&#x2019;s credit rating or the market&#x2019;s perception of the issuer&#x2019;s creditworthiness.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt;"&gt;Since it derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock, including the potential for increased volatility in the price of the convertible security.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_CorporateLoansRiskMember"
      id="t_51_02552978_505d_a88b_1957_b4ff251ef03b"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Corporate Loans Risk &lt;/span&gt;&lt;/span&gt;&#x2014; Commercial banks and other financial institutions or institutional investors make corporate loans to companies that need capital to grow or restructure. Borrowers generally pay interest on corporate loans at rates that change in response to changes in market interest rates such as the Secured Overnight Financing Rate (&#x201c;SOFR&#x201d;) or the prime rates of U.S. banks. As a result, the value of corporate loan investments is generally less exposed to the adverse effects of shifts in market interest rates than investments that pay a fixed rate of interest. The market for corporate loans may be subject to irregular trading activity and wide bid/ask spreads. In addition, transactions in corporate loans may settle on a delayed basis. As a result, the proceeds from the sale of corporate loans may not be readily available to make additional investments or to meet the Fund&#x2019;s redemption obligations. To the extent the extended settlement process gives rise to short-term liquidity needs, the Fund may hold additional cash, sell investments or temporarily borrow from banks and other lenders.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_DerivativesRisksMember"
      id="t_52_103a4ed3_fef5_cbea_8ea2_4d478fd47fba"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Derivatives Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The Fund&#x2019;s use of derivatives may increase its costs, reduce the Fund&#x2019;s returns and/or increase volatility. Derivatives involve significant risks, including:&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Leverage Risk&lt;/span&gt; &#x2014; The Fund&#x2019;s use of derivatives can magnify the Fund&#x2019;s gains and losses. Relatively small market movements may result in large changes in the value of a derivatives position and can result in losses that greatly exceed the amount originally invested.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Market Risk&lt;/span&gt; &#x2014; Some derivatives are more sensitive to interest rate changes and market price fluctuations than other securities. The Fund could also suffer losses related to its derivatives positions as a result of unanticipated market movements, which losses are potentially unlimited. Finally, BlackRock may not be able to predict correctly the direction of securities prices, interest rates and other economic factors, which could cause the Fund&#x2019;s derivatives positions to lose value.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Counterparty Risk&lt;/span&gt; &#x2014; Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will be unable or unwilling to fulfill its contractual obligation, and the related risks of having concentrated exposure to such a counterparty.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Illiquidity Risk&lt;/span&gt; &#x2014; The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Operational Risk&lt;/span&gt; &#x2014; The use of derivatives includes the risk of potential operational issues, including documentation issues, settlement issues, systems failures, inadequate controls and human error.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Legal Risk&lt;/span&gt; &#x2014; The risk of insufficient documentation, insufficient capacity or authority of counterparty, or legality or enforceability of a contract.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Volatility and Correlation Risk&lt;/span&gt; &#x2014; Volatility is defined as the characteristic of a security, an index or a market to fluctuate significantly in price within a short time period. A risk of the Fund&#x2019;s use of derivatives is that the fluctuations in their values may not correlate with the overall securities markets.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Valuation Risk&lt;/span&gt; &#x2014; Valuation for derivatives may not be readily available in the market. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Hedging Risk&lt;/span&gt; &#x2014; Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Fund&#x2019;s hedging transactions will be effective. The use of hedging may result in certain adverse tax consequences.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Tax Risk&lt;/span&gt; &#x2014; Certain aspects of the tax treatment of derivative instruments, including swap agreements and commodity-linked derivative instruments, are currently unclear and may be affected by changes in legislation, regulations or other legally binding authority. Such treatment may be less favorable than that given to a direct investment in an underlying asset and may adversely affect the timing, character and amount of income the Fund realizes from its investments.&lt;/div&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_EmergingMarketsRiskMember"
      id="t_53_41b1f1fd_7998_c8e9_d168_24738ad8c672"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Emerging Markets Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Emerging markets are riskier than more developed markets because they tend to develop unevenly and may never fully develop. Investments in emerging markets may be considered speculative. Emerging markets are more likely to experience hyperinflation and currency devaluations, which adversely affect returns to U.S. investors. In addition, many emerging financial markets have far lower trading volumes and less liquidity than developed markets.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_HighPortfolioTurnoverRiskMember"
      id="t_54_dedcb3d7_bf6c_7a27_22da_2c32cc03a01d"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;High Portfolio Turnover Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The Fund may engage in active and frequent trading of its portfolio securities. High portfolio turnover (more than 100%) may result in increased transaction costs to the Fund, including brokerage commissions, dealer mark-ups and other transaction costs on the sale of the securities and on reinvestment in other&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt;"&gt;securities. The sale of Fund portfolio securities may result in the realization and/or distribution to shareholders of higher capital gains or losses as compared to a fund with less active trading policies. These effects of higher than normal portfolio turnover may adversely affect Fund performance. In addition, investment in mortgage dollar rolls and participation in to-be-announced (&#x201c;TBA&#x201d;) transactions may significantly increase the Fund&#x2019;s portfolio turnover rate. A TBA transaction is a method of trading mortgage-backed securities where the buyer and seller agree upon general trade parameters such as agency, settlement date, par amount, and price at the time the contract is entered into but the mortgage-backed securities are delivered in the future, generally 30 days later.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_HighYieldBondsRiskMember"
      id="t_55_95f3aaa9_b02a_be2f_1aa2_1b2068f9d6d4"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;High Yield Bonds Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Although junk bonds generally pay higher rates of interest than investment grade bonds, junk bonds are high risk investments that are considered speculative and may cause income and principal losses for the Fund.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_IndexedAndInverseSecuritiesRiskMember"
      id="t_56_b927b066_a278_1760_7e47_e7c3aaa4d94f"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Indexed and Inverse Securities Risk &lt;/span&gt;&lt;/span&gt;&#x2014; Indexed and inverse securities provide a potential return based on a particular index of value or interest rates. The Fund&#x2019;s return on these securities will be subject to risk with respect to the value of the particular index. These securities are subject to leverage risk and correlation risk. Certain indexed and inverse securities have greater sensitivity to changes in interest rates or index levels than other securities, and the Fund&#x2019;s investment in such instruments may decline significantly in value if interest rates or index levels move in a way Fund management does not anticipate.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_LargeCapitalizationCompaniesRiskMember"
      id="t_57_20abc058_19e5_fbe1_c5c7_950b760f620f"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Large-Capitalization Companies Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Large-capitalization companies may be less able than smaller-capitalization companies to adapt to changing market conditions and competitive challenges. Large-capitalization companies may be more mature and subject to more limited growth potential compared with smaller-capitalization companies. The performance of large-capitalization companies could trail the overall performance of the broader securities markets.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_LeverageRiskMember"
      id="t_58_c9190294_8bac_a4ef_a43f_a7c8dbb7c557"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Leverage Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Some transactions may give rise to a form of economic leverage. These transactions may include, among others, derivatives, and may expose the Fund to greater risk and increase its costs. The use of leverage may cause the Fund to liquidate portfolio positions when it may not be advantageous to do so to satisfy its obligations or to meet the applicable requirements of the Investment Company Act of 1940, as amended (the &#x201c;Investment Company Act&#x201d;), and the rules thereunder. Increases and decreases in the value of the Fund&#x2019;s portfolio will be magnified when the Fund uses leverage.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_MarketRiskAndSelectionRiskMember"
      id="t_59_41830f03_7930_75af_dd16_1c89c56906b9"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Market Risk and Selection Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a security or other asset may decline due to changes in general market conditions, economic trends or events that are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its investments. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. The Fund seeks to pursue its investment objective by using proprietary models that incorporate quantitative analysis and is subject to &#x201c;Model Risk&#x201d; as described below. This means you may lose money.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_MidCapSecuritiesRiskMember"
      id="t_60_de63774b_4dd1_176a_13eb_886ebcde1a90"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Mid Cap Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The securities of mid cap companies generally trade in lower volumes and are generally subject to greater and less predictable price changes than the securities of larger capitalization companies. &lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt; &lt;/span&gt;&lt;/span&gt;&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_ModelRiskMember"
      id="t_61_d9634476_98e4_cab5_4409_70fa839df316"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Model Risk &lt;/span&gt;&lt;/span&gt;&#x2014; The Fund seeks to pursue its investment objective by using proprietary models that incorporate quantitative analysis. Investments selected using these models may perform differently than as forecasted due to the factors incorporated into the models and the weighting of each factor, changes from historical trends, and issues in the construction and implementation of the models (including, but not limited to, software issues, issues related to the use of artificial intelligence and machine learning (&#x201c;AI&#x201d;), and other technological issues). There is no guarantee that BlackRock&#x2019;s use of these models will result in effective investment decisions for the Fund.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;The information and data used in the models may be supplied by third parties. Inaccurate or incomplete data may limit the effectiveness of the models. In addition, some of the data that BlackRock uses may be historical data, which may not accurately predict future market movement. There is a risk that the models will not be successful in selecting investments or in determining the weighting of investment positions that will enable the Fund to achieve its investment objective.&lt;/div&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_MoneyMarketSecuritiesRiskMember"
      id="t_62_b15c70a1_0ac3_36be_9f9b_c49305dd9b4d"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Money Market Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; If market conditions improve while the Fund has invested some or all of its assets in high quality money market securities, this strategy could result in reducing the potential gain from the market upswing, thus reducing the Fund&#x2019;s opportunity to achieve its investment objective.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_MortgageAndAssetBackedSecuritiesRisksMember"
      id="t_77_54a04738_61c9_5a31_2ee9_960a25d5edd9">
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Mortgage- and Asset-Backed Securities Risks&lt;/span&gt;&lt;/span&gt; &#x2014; Mortgage- and asset-backed securities represent interests in &#x201c;pools&#x201d; of mortgages or other assets, including consumer loans or receivables held in trust. Mortgage- and asset&#x2011;backed securities are subject to credit, interest rate, prepayment and extension risks. These securities also are subject to risk of default on the underlying mortgage or asset, particularly during periods of economic downturn. Small movements in interest rates (both increases and decreases) may quickly and significantly reduce the value of certain mortgage-backed securities.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_MunicipalSecuritiesRisksMember"
      id="t_64_c68f54bf_6793_bf34_2185_2f77f012de05"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Municipal Securities Risks&lt;/span&gt;&lt;/span&gt;&lt;span style="font-style: italic;"&gt; &lt;/span&gt;&#x2014; Municipal securities risks include the ability of the issuer to repay the obligation, the relative lack of information about certain issuers of municipal securities, and the possibility of future legislative changes which could affect the market for and value of municipal securities. Budgetary constraints of local, state, and federal governments upon which the issuers may be relying for funding may also impact municipal securities. These risks include:&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;General Obligation Bonds Risks &lt;/span&gt;&#x2014; Timely payments depend on the issuer&#x2019;s credit quality, ability to raise tax revenues and ability to maintain an adequate tax base.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Revenue Bonds Risks &lt;/span&gt;&#x2014; These payments depend on the money earned by the particular facility or class of facilities, or the amount of revenues derived from another source.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Private Activity Bonds Risks &lt;/span&gt;&#x2014; Municipalities and other public authorities issue private activity bonds to finance development of industrial facilities for use by a private enterprise. The private enterprise pays the principal and interest on the bond, and the issuer does not pledge its full faith, credit and taxing power for repayment.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Moral Obligation Bonds Risks &lt;/span&gt;&#x2014; Moral obligation bonds are generally issued by special purpose public authorities of a state or municipality. If the issuer is unable to meet its obligations, repayment of these bonds becomes a moral commitment, but not a legal obligation, of the state or municipality.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Municipal Notes Risks &lt;/span&gt;&#x2014; Municipal notes are shorter term municipal debt obligations. If there is a shortfall in the anticipated proceeds, the notes may not be fully repaid and the Fund may lose money.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Municipal Lease Obligations Risks &lt;/span&gt;&#x2014; In a municipal lease obligation, the issuer agrees to make payments when due on the lease obligation. Although the issuer does not pledge its unlimited taxing power for payment of the lease obligation, the lease obligation is secured by the leased property.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Tax&#x2011;Exempt Status Risk &lt;/span&gt;&#x2014; The Fund and its investment manager will rely on the opinion of issuers&#x2019; bond counsel and, in the case of derivative securities, sponsors&#x2019; counsel, on the tax&#x2011;exempt status of interest on municipal bonds and payments under derivative securities. Neither the Fund nor its investment manager will independently review the bases for those tax opinions, which may ultimately be determined to be incorrect and subject the Fund and its shareholders to substantial tax liabilities.&lt;/div&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_NewIssuesRiskMember"
      id="t_65_d1d52cd3_ad29_dfcc_9629_09420a4c808a"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;&#x201c;New Issues&#x201d; Risk&lt;/span&gt;&lt;/span&gt; &#x2014; &#x201c;New issues&#x201d; are IPOs of equity securities. Securities issued in IPOs have no trading history, and information about the companies may be available for very limited periods. In addition, the prices of securities sold in IPOs may be highly volatile or may decline shortly after the IPO.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_OperationalAndTechnologyRisksMember"
      id="t_66_d1012f04_3db5_7807_4c4d_5983aa131037"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Operational and Technology Risks&lt;/span&gt;&lt;/span&gt; &#x2014; The Fund is directly and indirectly susceptible to operational and technology risks, including those related to human errors, processing errors, communication errors, systems failures, cybersecurity incidents, and the use of artificial intelligence and machine learning (&#x201c;AI&#x201d;), which may result in losses for the Fund and its shareholders or may impair the Fund&#x2019;s operations. While the Fund&#x2019;s service providers are required to have appropriate operational, information security and cybersecurity risk management policies and procedures, their methods of risk management may differ from those of the Fund. Operational and technology risks for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and may cause the Fund&#x2019;s investments in such issuers to lose value.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_PreferredSecuritiesRiskMember"
      id="t_67_edcc4af1_6b13_0769_d21a_852fa226f861"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Preferred Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Preferred securities may pay fixed or adjustable rates of return. Preferred securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company&#x2019;s preferred securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company&#x2019;s financial condition or prospects. Preferred securities of smaller companies may be more vulnerable to adverse developments than preferred securities of larger companies.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_SmallCapAndEmergingGrowthSecuritiesRiskMember"
      id="t_68_bcb34e95_c4c2_8b5d_3858_c0f0f6d90ae3"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Small Cap and Emerging Growth Securities Risk &lt;/span&gt;&lt;/span&gt;&#x2014; Small cap or emerging growth companies may have limited product lines or markets. They may be less financially secure than larger, more established companies. They may depend on a more limited management group than larger capitalized companies.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_SovereignDebtRiskMember"
      id="t_69_cd6628ac_c902_3e96_a380_c51fa1c7a8dc"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Sovereign Debt Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Sovereign debt instruments are subject to the risk that a governmental entity may delay or refuse to pay interest or repay principal on its sovereign debt, due, for example, to cash flow problems, insufficient foreign currency reserves, political considerations, the relative size of the governmental entity&#x2019;s debt position in relation to the economy or the failure to put in place economic reforms required by the International Monetary Fund or other multilateral agencies.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_StructuredSecuritiesRiskMember"
      id="t_70_395fb5a4_d8fa_63e9_e280_74e1fbd3ac83"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Structured Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Because structured securities of the type in which the Fund may invest typically involve no credit enhancement, their credit risk generally will be equivalent to that of the underlying instruments, index or reference obligation and will also be subject to counterparty risk. The Fund may have the right to receive payments only from the structured security, and generally does not have direct rights against the issuer or the entity that sold the assets to be securitized. In addition to the general risks associated with debt securities discussed herein, structured securities carry additional risks, including, but not limited to: the possibility that distributions from&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt;"&gt;collateral securities will not be adequate to make interest or other payments; the quality of the collateral may decline in value or default; and the possibility that the structured securities are subordinate to other classes. The Fund is permitted to invest in a class of structured securities that is either subordinated or unsubordinated to the right of payment of another class. Subordinated structured securities typically have higher yields and present greater risks than unsubordinated structured securities. Structured securities are typically sold in private placement transactions, and there currently is no active trading market for structured securities. Structured securities are based upon the movement of one or more factors, including currency exchange rates, interest rates, reference bonds and stock indices, and changes in interest rates and impact of these factors may cause significant price fluctuations. Additionally, changes in the reference instrument or security may cause the interest rate on the structured security to be reduced to zero. Certain issuers of such structured securities may be deemed to be &#x201c;investment companies&#x201d; as defined in the Investment Company Act. As a result, the Fund&#x2019;s investment in such securities may be limited by certain investment restrictions contained in the Investment Company Act.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_USGovernmentIssuerRiskMember"
      id="t_71_9beef1bf_57ea_70c7_421b_b16d3090b059"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;U.S. Government Issuer Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Treasury obligations may differ in their interest rates, maturities, times of issuance and other characteristics. Obligations of U.S. Government agencies and authorities are supported by varying degrees of credit but generally are not backed by the full faith and credit of the U.S. Government. No assurance can be given that the U.S. Government will provide financial support to its agencies and authorities if it is not obligated by law to do so.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003863Member_USGovernmentMortgageRelatedSecuritiesRiskMember"
      id="t_72_8504b96c_680c_4590_096f_a297888d3a5f"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;U.S. Government Mortgage-Related Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; There are a number of important differences among the agencies and instrumentalities of the U.S. Government that issue mortgage-related securities and among the securities that they issue. Mortgage-related securities guaranteed by the Government National Mortgage Association (&#x201c;GNMA&#x201d; or &#x201c;Ginnie Mae&#x201d;) are guaranteed as to the timely payment of principal and interest by GNMA and such guarantee is backed by the full faith and credit of the United States. GNMA securities also are supported by the right of GNMA to borrow funds from the U.S. Treasury to make payments under its guarantee. Mortgage-related securities issued by Fannie Mae or Freddie Mac are solely the obligations of Fannie Mae or Freddie Mac, as the case may be, and are not backed by or entitled to the full faith and credit of the United States but are supported by the right of the issuer to borrow from the Treasury.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="S000003863Member"
      id="t_33_1ded4ccd_eca9_4cdf_8a83_3c1a398e7f48"> Performance Information  </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="S000003863Member"
      id="t_34_9b1efdff_8e84_4eb4_b61e_537a6f16cbd7"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;Effective May 1, 2025, the Fund changed its name, investment process and investment strategies. Effective April 8, 2022, the Fund changed its name, investment process and investment strategies. Performance for the periods prior to April 8, 2022 shown below is based on the investment process and investment strategies utilized by the Fund under the name &#x201c;BlackRock Balanced Capital Portfolio.&#x201d;&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The information shows you how the Fund&#x2019;s performance has varied year by year and provides some indication of the risks of investing in the Fund. The table compares the Fund&#x2019;s performance to that of the MSCI All Country World Index (Net), the Bloomberg U.S. Aggregate Bond Index and a customized weighted index comprised of the returns of the MSCI All Country World Index (Net) (60%)&#160;and the Bloomberg U.S. Aggregate Bond Index (40%), which are relevant to the Fund because they have characteristics similar to the Fund&#x2019;s investment strategies. To the extent that dividends and distributions have been paid by the Fund, the performance information for the Fund in the chart and table assumes reinvestment of the dividends and distributions. As with all such investments, past performance is not an indication of future results. The bar chart and table do not reflect separate account fees and expenses. If they did, returns would be less than those shown. If the Fund&#x2019;s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund&#x2019;s returns would have been lower.&lt;/div&gt; </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="S000003863Member"
      id="t_40_c701e13a_a305_d85a_273d_a25d85b7ad48">The information shows you how the Fund&#x2019;s performance has varied year by year and provides some indication of the risks of investing in the Fund.</oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformanceAdditionalMarketIndex
      contextRef="S000003863Member"
      id="t_41_42c373fc_6950_f8a5_84af_eb9530801580">The table compares the Fund&#x2019;s performance to that of the MSCI All Country World Index (Net), the Bloomberg U.S. Aggregate Bond Index and a customized weighted index comprised of the returns of the MSCI All Country World Index (Net) (60%)&#160;and the Bloomberg U.S. Aggregate Bond Index (40%), which are relevant to the Fund because they have characteristics similar to the Fund&#x2019;s investment strategies.</oef:PerformanceAdditionalMarketIndex>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="S000003863Member"
      id="t_42_f593cf5a_6704_03f2_b5a6_4ffaeda849f7">As with all such investments, past performance is not an indication of future results.</oef:PerformancePastDoesNotIndicateFuture>
    <oef:BarChartDoesNotReflectSalesLoads
      contextRef="S000003863Member"
      id="t_43_dceb2145_67cd_5d69_a7b7_857d3c282575">The bar chart and table do not reflect separate account fees and expenses. If they did, returns would be less than those shown.</oef:BarChartDoesNotReflectSalesLoads>
    <oef:BarChartHeading
      contextRef="S000003863Member"
      id="t_35_638de01e_ea32_4b71_991f_755f68350656"> ANNUAL TOTAL RETURNS  BlackRock Balanced Portfolio  As of 12/31 </oef:BarChartHeading>
    <oef:BarChartClosingTextBlock
      contextRef="S000003863Member"
      id="t_44_a734d6a4_3844_cd17_fa24_d9ee6795407f"> &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;During the ten-year period shown in the bar chart, the highest return for a quarter was 15.78% (quarter ended June&#160;30, 2020) and the lowest return for a quarter was -13.30% (quarter ended March 31, 2020).&lt;/div&gt; </oef:BarChartClosingTextBlock>
    <oef:HighestQuarterlyReturnLabel
      contextRef="S000003863Member_C000010829Member"
      id="t_73_63089120_0cb1_0eee_f941_543a84a405c8">highest return</oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="S000003863Member_C000010829Member"
      decimals="4"
      id="h_33_99b7d1a9_301c_17cc_1117_5d8cb1b1b525"
      unitRef="pure">0.1578</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="S000003863Member_C000010829Member"
      id="t_76_81240722_e133_84d9_d856_199f2cad1199">2020-06-30</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="S000003863Member_C000010829Member"
      id="t_74_34a6c623_acde_13e5_cc29_102dfed88583">lowest return</oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="S000003863Member_C000010829Member"
      decimals="4"
      id="h_32_6fb0e053_f6a6_25b8_ee95_f55a5155a36a"
      unitRef="pure">-0.1330</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="S000003863Member_C000010829Member"
      id="t_75_39ffe0e9_a882_592e_1262_cea2cd3aa815">2020-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:PerformanceTableHeading
      contextRef="S000003863Member"
      id="t_45_07e70c04_c2d3_f422_8920_ee782e69dc30">For the periods ended 12/31/25Average Annual Total Returns</oef:PerformanceTableHeading>
    <oef:AvgAnnlRtrPct
      contextRef="FY2025_C000010829Member"
      decimals="4"
      id="h_34_7eb9fa01_5ad2_abe1_ea3c_85a3f4e8304c"
      unitRef="pure">0.1567</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FiveY2025_C000010829Member"
      decimals="4"
      id="h_38_ed0fd4fe_8da7_c1a6_6f8b_307927774d05"
      unitRef="pure">0.0839</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="TenY2025_C000010829Member"
      decimals="4"
      id="h_42_b72d4e53_e019_9e00_e85e_43a8c3342114"
      unitRef="pure">0.0986</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FY2025_MSCIAllCountryWorldIndexMember"
      decimals="4"
      id="h_35_7b7ae065_0449_e942_eb32_ac4443382332"
      unitRef="pure">0.2234</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FiveY2025_MSCIAllCountryWorldIndexMember"
      decimals="4"
      id="h_39_9056052d_ecc6_cd8c_0423_96ec90050f92"
      unitRef="pure">0.1119</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="TenY2025_MSCIAllCountryWorldIndexMember"
      decimals="4"
      id="h_43_41d28db8_bb56_40b7_e9fa_13882b96bcfb"
      unitRef="pure">0.1172</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FY2025_BloombergUSAggregateBondIndexMember"
      decimals="4"
      id="h_36_71fd0139_52f2_62b9_95b8_a21d1e2d139e"
      unitRef="pure">0.0730</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FiveY2025_BloombergUSAggregateBondIndexMember"
      decimals="4"
      id="h_40_5a3045d0_bb07_314f_64ee_7e079d18cbde"
      unitRef="pure">-0.0036</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="TenY2025_BloombergUSAggregateBondIndexMember"
      decimals="4"
      id="h_44_afd7d541_5482_2673_e9eb_d7563554656a"
      unitRef="pure">0.0201</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FY2025_SixtyMSCIAllCountryWorldIndexMember"
      decimals="4"
      id="h_37_63498e92_7525_eacc_3945_4fded2ec1fbb"
      unitRef="pure">0.1622</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FiveY2025_SixtyMSCIAllCountryWorldIndexMember"
      decimals="4"
      id="h_41_a0339498_0628_807e_3e86_a9df9219d671"
      unitRef="pure">0.0657</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="TenY2025_SixtyMSCIAllCountryWorldIndexMember"
      decimals="4"
      id="h_45_db871fc7_0f91_1ad2_0f5c_5055a06b7bc4"
      unitRef="pure">0.0796</oef:AvgAnnlRtrPct>
    <oef:RiskReturnHeading
      contextRef="S000003867Member"
      id="t_51_aae27d22_7c8c_118f_6675_b06de041e24b">Fund Overview Key Facts About BlackRock Capital Appreciation Portfolio </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="S000003867Member"
      id="t_52_ec4b06a3_40ca_a9f4_e620_af72d5967e77">Investment Objective</oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="S000003867Member"
      id="t_40_c61a3f0e_7331_4aa7_9894_065dbbecf075"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The investment objective of BlackRock Capital Appreciation Portfolio (the &#x201c;Capital Appreciation Portfolio&#x201d; or the &#x201c;Fund&#x201d;), a series of BlackRock Series Fund, Inc. (the &#x201c;Corporation&#x201d;), is to seek long-term growth of capital.&lt;/div&gt; </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="S000003867Member"
      id="t_53_70a06bce_3cc8_359a_c70f_08c391e45e1b">Fees and Expenses of the Fund</oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="S000003867Member"
      id="t_42_bc541239_b09f_41d1_a0b8_b627d08e1e7f"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. &lt;span style="font-weight: bold;"&gt;The table and example below do not include separate account fees and expenses, and expenses would be higher if these fees and expenses were included.&lt;/span&gt; Please refer to your variable annuity or insurance contract (the &#x201c;Contract&#x201d;) prospectus for information on the separate account fees and expenses associated with your Contract.&lt;/div&gt; </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="S000003867Member"
      id="t_43_1c4d49c2_2c06_4b7a_a69c_d8ffde62bc19"> Shareholder Fees (fees paid directly from your investment)  The Fund is not subject to any Shareholder Fees. </oef:ShareholderFeesCaption>
    <oef:OperatingExpensesCaption
      contextRef="S000003867Member"
      id="t_44_63180413_833c_405b_82fe_03c28152eec9"> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="S000003867Member_C000010833Member"
      decimals="4"
      id="h_32_c0ae3bc4_c160_4ef5_afce_fc01c59dbd09"
      unitRef="pure">0.0037</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="S000003867Member_C000010833Member"
      decimals="4"
      id="h_33_40a34db1_76b1_401b_85e2_df7c81220347"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="S000003867Member_C000010833Member"
      decimals="4"
      id="h_34_bc25ffe7_d415_495a_99a1_bc75f7b82d7f"
      unitRef="pure">0.0020</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="S000003867Member_C000010833Member"
      decimals="4"
      id="h_35_3cf35994_c2e7_4e50_98da_62b9cec6c1aa"
      unitRef="pure">0.0057</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="S000003867Member_C000010833Member"
      decimals="4"
      id="h_36_a80ec020_5434_4011_a643_89ca75bf4cdf"
      unitRef="pure">-0.0010</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="S000003867Member_C000010833Member"
      decimals="4"
      id="h_37_40add80f_4ae9_477e_83c2_1dba09fdb6a7"
      unitRef="pure">0.0047</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="S000003867Member"
      id="t_54_de5656fc_4470_6076_fd71_67ecc3e33759">June 30, 2027</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpenseExampleHeading
      contextRef="S000003867Member"
      id="t_45_ba2c9b1e_248c_4adb_b887_778b5e5209e3"> Example: </oef:ExpenseExampleHeading>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="S000003867Member"
      id="t_46_0d26a8c0_70f0_4796_b20e_98604d122dcc"> &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund&#x2019;s operating expenses remain the same. The Example does not reflect charges imposed by the Contract. See the Contract prospectus for information on such charges. Although your actual costs may be higher or lower, based on these assumptions your costs would be:&lt;/div&gt; </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="S000003867Member_C000010833Member"
      decimals="INF"
      id="h_38_a2599ee0_030a_4b29_9815_218fb9b97b24"
      unitRef="USD">48</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="S000003867Member_C000010833Member"
      decimals="INF"
      id="h_39_9d614213_8eaa_4f6b_b4e9_e16f7fb34956"
      unitRef="USD">173</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="S000003867Member_C000010833Member"
      decimals="INF"
      id="h_40_b1313f07_9347_4a1a_8176_a046edb9d100"
      unitRef="USD">308</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="S000003867Member_C000010833Member"
      decimals="INF"
      id="h_41_b99fa792_7d15_42db_a8b7_44c4b622fa2e"
      unitRef="USD">704</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="S000003867Member"
      id="t_47_f80c5dbe_a413_433b_a1f6_0cfefdce292d"> Portfolio Turnover: </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="S000003867Member"
      id="t_48_70c6ba88_bf6b_407e_8e4b_a43b98c7baa6"> &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund pays transaction costs, such as commissions, when it buys and sells securities (or &#x201c;turns over&#x201d; its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund&#x2019;s performance. During the most recent fiscal year, the Fund&#x2019;s portfolio turnover rate was 65% of the average value of its portfolio.&lt;/div&gt; </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="S000003867Member"
      decimals="4"
      id="h_42_85a3b665_d338_450d_9475_21a4bf930ff8"
      unitRef="pure">0.65</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="S000003867Member"
      id="t_55_4143aa86_dfca_43bf_5824_fe7c290966db">Principal Investment Strategies of the Fund</oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="S000003867Member"
      id="t_50_1325cd72_4867_446c_9cd4_9a141bdf38de"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund will seek to achieve its investment objective by investing primarily in a diversified portfolio consisting primarily of common stock of U.S. companies that Fund management believes have exhibited above-average growth rates in earnings over the long term. In other words, Fund management tries to choose investments that will increase in value over the long term.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund will generally invest at least 65% of its total assets in the following equity securities:&lt;/div&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;Common stock;&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;Convertible preferred stock; and&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;Rights to subscribe to common stock.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;Of these securities, the Fund generally seeks to invest primarily in common stock. The Fund may also purchase securities convertible into common stock.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund may invest in companies of any size but emphasizes investments in companies that have large stock market capitalizations (currently, approximately $2&#160;billion or more). The Fund may invest across different market sectors and industries, and at times may have material investment exposure to one or more sectors or industries.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;Convertible securities generally are debt securities or preferred stock that may be converted into common stock. Convertible securities typically pay current income as either interest (debt security convertibles) or dividends (preferred stock). A convertible&#x2019;s value usually reflects both the stream of current income payments and the market value of the underlying common stock. The Fund may purchase securities pursuant to the exercise of subscription rights, which allow an issuer&#x2019;s existing shareholders to purchase additional common stock at a price substantially below the market price of the shares.&lt;/div&gt; </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003867Member_RiskLoseMoneyMember"
      id="t_56_e144411e_d444_7e9e_c97c_1bed99158351">You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003867Member_EquitySecuritiesRiskMember"
      id="t_57_8b663109_6471_5c63_f099_b625d81f6749"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Equity Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Stock markets are volatile. The price of equity securities fluctuates based on changes in a company&#x2019;s financial condition and overall market and economic conditions.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003867Member_InvestmentStyleRiskMember"
      id="t_58_6323991e_2944_71d4_927d_733113859179"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Investment Style Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Under certain market conditions, growth investments have performed better during the later stages of economic expansion. Therefore, this investment style may over time go in and out of favor. At times when the investment style used by the Fund is out of favor, the Fund may underperform other equity funds that use different investment styles.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003867Member_MarketRiskAndSelectionRiskMember"
      id="t_59_87cdb317_cca4_e7f3_34b1_68fafc2f461a"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Market Risk and Selection Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a security or other asset may decline due to changes in general market conditions, economic trends or events that are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its investments. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003867Member_ConvertibleSecuritiesRiskMember"
      id="t_60_b036deff_b743_31bd_a98a_35a14cdb9c56"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Convertible Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The market value of a convertible security performs like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest, principal or dividends when due, and their market value may change based on changes in the issuer&#x2019;s credit rating or the market&#x2019;s perception of the issuer&#x2019;s creditworthiness. Since it derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock, including the potential for increased volatility in the price of the convertible security.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003867Member_SectorRiskMember"
      id="t_61_deb6a22b_baa6_af1a_0a29_f9c6a0414b59"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-style: italic;"&gt;&lt;/span&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Sector Risk&lt;/span&gt;&lt;/span&gt;&lt;span style="font-style: italic;"&gt;&lt;/span&gt; &#x2014; Sector risk is the risk that the Fund&#x2019;s investments in the securities of companies in a specific market sector or industry will cause the Fund to be more exposed to the price movements of companies in, and developments affecting, that sector. To the extent that the Fund invests significantly in a particular sector or industry, there is the risk that the Fund will perform poorly during a downturn in that sector or underperform other funds that are more broadly diversified across sectors and industries.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003867Member_MidCapSecuritiesRiskMember"
      id="t_62_c491d862_a231_0a4e_87f3_9c2bd24de51a"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Mid Cap Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The securities of mid cap companies generally trade in lower volumes and are generally subject to greater and less predictable price changes than the securities of larger capitalization companies.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003867Member_LargeCapitalizationCompaniesRiskMember"
      id="t_63_53dda3d4_ca2d_30ec_8ee6_36c1a2127928"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Large-Capitalization Companies Risk &lt;/span&gt;&lt;/span&gt;&#x2014; Large-capitalization companies may be less able than smaller- capitalization companies to adapt to changing market conditions and competitive challenges. Large-capitalization companies may be more mature and subject to more limited growth potential compared with smaller-capitalization companies. The performance of large-capitalization companies could trail the overall performance of the broader securities markets.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003867Member_PreferredSecuritiesRiskMember"
      id="t_64_2aa24806_25a3_04aa_5077_dc0c1448aafd"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Preferred Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Preferred securities may pay fixed or adjustable rates of return. Preferred securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company&#x2019;s preferred securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company&#x2019;s financial condition or prospects. Preferred securities of smaller companies may be more vulnerable to adverse developments than preferred securities of larger companies.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003867Member_RightsRiskMember"
      id="t_65_bde89a56_3636_481a_e267_553ea83a56ae"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Rights Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The failure to exercise subscription rights to purchase common stock would result in the dilution of the Fund&#x2019;s interest in the issuing company. The market for such rights is not well developed, and, accordingly, the Fund may not always realize full value on the sale of rights.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003867Member_RiskOfInvestingInTheUnitedStatesMember"
      id="t_66_3bbdc173_cb4a_7c83_7b88_98d15edeeac2"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Risk of Investing in the United States&lt;/span&gt;&lt;/span&gt; &#x2014; Certain changes in the U.S. economy, such as when the U.S. economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003867Member_OperationalAndTechnologyRisksMember"
      id="t_67_75dce573_e59c_f9d2_c782_fb724b474df7"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Operational and Technology Risks &lt;/span&gt;&lt;/span&gt;&#x2014; The Fund is directly and indirectly susceptible to operational and technology risks, including those related to human errors, processing errors, communication errors, systems failures, cybersecurity incidents, and the use of artificial intelligence and machine learning (&#x201c;AI&#x201d;), which may result in losses for the Fund and its shareholders or may impair the Fund&#x2019;s operations. While the Fund&#x2019;s service providers are required to have appropriate operational, information security and cybersecurity risk management policies and procedures, their methods of risk management may differ from those of the Fund. Operational and technology risks for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and may cause the Fund&#x2019;s investments in such issuers to lose value.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="S000003867Member"
      id="t_68_8b662233_5be8_724b_3ee5_6f6cbf143db0">Performance Information</oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="S000003867Member"
      id="t_73_d1c63a63_5659_4a7b_a54b_c7f9eaa1949a"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The information shows you how the Fund&#x2019;s performance has varied year by year and provides some indication of the risks of investing in the Fund. The table compares the Fund&#x2019;s performance to that of the S&amp;amp;P 500&lt;sup style="font-size: 75%; vertical-align: top;"&gt;&#xae;&lt;/sup&gt; Index and the Russell 1000&lt;sup style="font-size: 75%; vertical-align: top;"&gt;&#xae;&lt;/sup&gt; Growth Index, which are relevant to the Fund because they have characteristics similar to the Fund&#x2019;s investment strategies. To the extent that dividends and distributions have been paid by the Fund, the performance information for the Fund in the chart and table assumes reinvestment of the dividends and distributions. As with all such investments, past performance is not an indication of future results. The bar chart and table do not reflect separate account fees and expenses. If they did, returns would be less than those shown. If the Fund&#x2019;s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund&#x2019;s returns would have been lower.&lt;/div&gt; </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="S000003867Member"
      id="t_69_bf5d07be_d4f7_ddfa_ae7f_1e306dd58bd2">The information shows you how the Fund&#x2019;s performance has varied year by year and provides some indication of the risks of investing in the Fund.</oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformanceAdditionalMarketIndex
      contextRef="S000003867Member"
      id="t_70_c53c040c_3175_fc72_fd09_0e2f1ec97ee0">The table compares the Fund&#x2019;s performance to that of the S&amp;P 500&#xae; Index and the Russell 1000&#xae; Growth Index, which are relevant to the Fund because they have characteristics similar to the Fund&#x2019;s investment strategies.</oef:PerformanceAdditionalMarketIndex>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="S000003867Member"
      id="t_71_14be01af_146f_bbfd_ea6d_410a14986e35">As with all such investments, past performance is not an indication of future results.</oef:PerformancePastDoesNotIndicateFuture>
    <oef:BarChartDoesNotReflectSalesLoads
      contextRef="S000003867Member"
      id="t_72_a50fc3b9_c706_b1c5_0e4e_e2bb186773f6">The bar chart and table do not reflect separate account fees and expenses. If they did, returns would be less than those shown.</oef:BarChartDoesNotReflectSalesLoads>
    <oef:BarChartHeading
      contextRef="S000003867Member"
      id="t_74_10b120e7_44b0_d63c_4ef9_4368da6288ea"> ANNUAL TOTAL RETURNS  BlackRock Capital Appreciation Portfolio  As of 12/31 </oef:BarChartHeading>
    <oef:BarChartClosingTextBlock
      contextRef="S000003867Member"
      id="t_79_f23e1d66_37bc_28a8_3fdc_07139cb9ed6e"> &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;During the ten&#x2011;year period shown in the bar chart, the highest return for a quarter was 29.04% (quarter ended June 30, 2020) and the lowest return for a quarter was -23.10% (quarter ended June 30, 2022).&lt;/div&gt; </oef:BarChartClosingTextBlock>
    <oef:HighestQuarterlyReturnLabel
      contextRef="S000003867Member_C000010833Member"
      id="t_75_fa5b2737_259f_53e6_100c_0c18b93c92f6">highest return</oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="S000003867Member_C000010833Member"
      decimals="4"
      id="h_52_2defba91_31cd_f59b_9582_7734c4e0d024"
      unitRef="pure">0.2904</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="S000003867Member_C000010833Member"
      id="t_76_cbacd43f_5b45_a02c_0516_b5261ed47131">2020-06-30</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="S000003867Member_C000010833Member"
      id="t_77_6f4aa52f_f68e_ac09_0ddd_0a2ae80a0f0a">lowest return</oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="S000003867Member_C000010833Member"
      decimals="4"
      id="h_53_f2d8f45c_c9d7_50bd_5fc9_c4639c59b009"
      unitRef="pure">-0.2310</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="S000003867Member_C000010833Member"
      id="t_78_5ad3121d_3d85_b3d9_7a1d_4c4ccbb49c5e">2022-06-30</oef:BarChartLowestQuarterlyReturnDate>
    <oef:PerformanceTableHeading
      contextRef="S000003867Member"
      id="t_80_b596e209_f465_74b3_cf93_d694653d11d9">For the periods ended 12/31/25Average Annual Total Returns</oef:PerformanceTableHeading>
    <oef:AvgAnnlRtrPct
      contextRef="FY2025_C000010833Member"
      decimals="4"
      id="h_43_e02343cf_1bba_47a8_acdf_a6c8faad89a3"
      unitRef="pure">0.1204</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FiveY2025_C000010833Member"
      decimals="4"
      id="h_44_22b37df2_6204_4981_896b_58880772b98d"
      unitRef="pure">0.1077</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="TenY2025_C000010833Member"
      decimals="4"
      id="h_45_fdf33606_d75f_4b6a_96b3_83ae56c6252d"
      unitRef="pure">0.1561</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FY2025_SAndP500IndexMember"
      decimals="4"
      id="h_46_e7564857_73f0_4d79_8c7a_15668b862f69"
      unitRef="pure">0.1788</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FiveY2025_SAndP500IndexMember"
      decimals="4"
      id="h_47_6b76b6a4_8884_428b_ae9c_194d305d4769"
      unitRef="pure">0.1442</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="TenY2025_SAndP500IndexMember"
      decimals="4"
      id="h_48_9b22bd3b_8321_40e1_b16c_5f3b661786c2"
      unitRef="pure">0.1482</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FY2025_Russell1000GrowthIndexMember"
      decimals="4"
      id="h_49_d409d86b_394a_4029_9061_8df5c92ce428"
      unitRef="pure">0.1856</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FiveY2025_Russell1000GrowthIndexMember"
      decimals="4"
      id="h_50_1ddcc691_20fa_4ab0_8e4f_0f6788cb0416"
      unitRef="pure">0.1532</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="TenY2025_Russell1000GrowthIndexMember"
      decimals="4"
      id="h_51_87e81a72_49f6_494e_8d75_c27348d27177"
      unitRef="pure">0.1813</oef:AvgAnnlRtrPct>
    <oef:RiskReturnHeading
      contextRef="S000003866Member"
      id="t_103_329a0dbb_73b4_7d0b_aa00_3f889d14305d">Fund Overview Key Facts About BlackRock Global Allocation Portfolio </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="S000003866Member"
      id="t_104_56eb80dc_0b7a_107e_3ce8_764a98bf7c32">Investment Objective</oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="S000003866Member"
      id="t_59_39bc4a60_521f_4e03_9557_a1ae7c226fa7"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The investment objective of BlackRock Global Allocation Portfolio (the &#x201c;Global Allocation Portfolio&#x201d; or the &#x201c;Fund&#x201d;), a series of BlackRock Series Fund, Inc. (the &#x201c;Corporation&#x201d;), is to seek high total investment return.&lt;/div&gt; </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="S000003866Member"
      id="t_105_79db142f_a42e_2f0d_9942_1e07fcfcbdf2">Fees and Expenses of the Fund</oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="S000003866Member"
      id="t_61_e5e3cc0a_acde_4647_a7a3_d9fc6606bb6b"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. &lt;span style="font-weight: bold;"&gt;The table and example below do not include separate account fees and expenses, and expenses would be higher if these fees and expenses were included.&lt;/span&gt; Please refer to your variable annuity or insurance contract (the &#x201c;Contract&#x201d;) prospectus for information on the separate account fees and expenses associated with your Contract.&lt;/div&gt; </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="S000003866Member"
      id="t_62_2a44a2e2_b7dd_4018_9b75_47230a977cf5"> Shareholder Fees (fees paid directly from your investment)  The Fund is not subject to any Shareholder Fees. </oef:ShareholderFeesCaption>
    <oef:OperatingExpensesCaption
      contextRef="S000003866Member"
      id="t_63_4cc48bd6_d4da_4e5c_8e28_6440ae132006">Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)</oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="S000003866Member_C000010832Member"
      decimals="4"
      id="h_52_0e208927_775b_4d6b_906b_9518bd825f7d"
      unitRef="pure">0.0037</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="S000003866Member_C000010832Member"
      decimals="4"
      id="h_53_b49f830a_27cc_4f93_abb9_26c41eeaaa4c"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="S000003866Member_C000010832Member"
      decimals="4"
      id="h_54_c32b31f7_b77d_4d96_a4ea_3c6a53d3f50d"
      unitRef="pure">0.0056</oef:OtherExpensesOverAssets>
    <oef:AcquiredFundFeesAndExpensesOverAssets
      contextRef="S000003866Member_C000010832Member"
      decimals="4"
      id="h_55_8d48e301_649d_4a38_b1fc_c2285f206763"
      unitRef="pure">0.0003</oef:AcquiredFundFeesAndExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="S000003866Member_C000010832Member"
      decimals="4"
      id="h_56_b34b849a_4080_40aa_b233_59b51751b459"
      unitRef="pure">0.0096</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="S000003866Member_C000010832Member"
      decimals="4"
      id="h_57_5a50c4e8_e2d3_49d4_a592_f92cdca56db0"
      unitRef="pure">-0.0036</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="S000003866Member_C000010832Member"
      decimals="4"
      id="h_58_f84cbe3e_6420_4f9f_b5e1_a5b61560caa0"
      unitRef="pure">0.0060</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="S000003866Member"
      id="t_106_32844728_046f_2d7e_d88f_2b0a9beb9613">June&#160;30, 2027</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpensesNotCorrelatedToRatioDueToAcquiredFundFees
      contextRef="S000003866Member"
      id="t_107_7f96620b_a9c7_282b_3f25_96e2ab8e9173">The Total Annual Fund Operating Expenses does not correlate to the ratio of expenses to average net assets given in the Fund&#x2019;s most recent Annual Financial Statements and Additional Information, which does not include Acquired Fund Fees and Expenses.</oef:ExpensesNotCorrelatedToRatioDueToAcquiredFundFees>
    <oef:ExpenseExampleHeading
      contextRef="S000003866Member"
      id="t_64_e800f8a4_be8d_445b_868b_00d243fad04c"> Example: </oef:ExpenseExampleHeading>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="S000003866Member"
      id="t_65_cdbccbb4_4f20_45b4_bd77_9c34597bf941"> &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund&#x2019;s operating expenses remain the same. The Example does not reflect charges imposed by the Contract. See the Contract prospectus for information on such charges. Although your actual costs may be higher or lower, based on these assumptions your costs would be:&lt;/div&gt; </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="S000003866Member_C000010832Member"
      decimals="INF"
      id="h_59_4aae71fd_b6a5_4b93_a0bd_0b3d7494660d"
      unitRef="USD">61</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="S000003866Member_C000010832Member"
      decimals="INF"
      id="h_60_74eece6a_179c_4dea_8e13_33731b1009f2"
      unitRef="USD">270</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="S000003866Member_C000010832Member"
      decimals="INF"
      id="h_61_f2a40c43_7bc1_43a4_8abc_db9b77c93ac7"
      unitRef="USD">496</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="S000003866Member_C000010832Member"
      decimals="INF"
      id="h_62_4b23b9c4_c1e2_4629_9766_e6a231fefc32"
      unitRef="USD">1145</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="S000003866Member"
      id="t_66_b1d7607d_6c3a_4571_9ec8_310283cc0bcc"> Portfolio Turnover: </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="S000003866Member"
      id="t_67_1e5ed8b0_3036_4d69_a206_132302943f6e"> &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund pays transaction costs, such as commissions, when it buys and sells securities (or &#x201c;turns over&#x201d; its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when shares are&lt;/div&gt;  &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund&#x2019;s performance. During the most recent fiscal year, the Fund&#x2019;s portfolio turnover rate was 124% of the average value of its portfolio.&lt;/div&gt; </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="S000003866Member"
      decimals="4"
      id="h_63_ad315c6c_1cf2_40a0_bf28_6ab540253eaf"
      unitRef="pure">1.24</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="S000003866Member"
      id="t_108_bd53f2c1_f64b_ccb4_6a29_6f571075db4b">Principal Investment Strategies of the Fund</oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="S000003866Member"
      id="t_69_de78d89f_b4aa_4e02_8e19_e68c1d9f2c1c"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund invests in a portfolio of equity, debt and money market securities. Generally, the Fund&#x2019;s portfolio will include both equity and debt securities. Equity securities include common stock, preferred stock, rights and warrants or securities or other instruments whose price is linked to the value of common stock. At any given time, however, the Fund may emphasize either debt securities or equity securities. In selecting equity investments, the Fund mainly seeks securities that Fund management believes are undervalued. The Fund may buy debt securities of varying maturities, debt securities paying a fixed or fluctuating rate of interest, and debt securities of any kind, including, by way of example, securities issued or guaranteed by the U.S. Government or its agencies or instrumentalities, by foreign governments or international agencies or supranational entities, or by domestic or foreign private issuers, debt securities convertible into equity securities, inflation-indexed bonds, structured notes, credit-linked notes, loan assignments and loan participations. In addition, the Fund may invest up to 35% of its total assets in &#x201c;junk bonds,&#x201d; corporate loans and distressed securities. The Fund may also invest in real estate investment trusts (&#x201c;REITs&#x201d;) and securities related to real assets (like real estate- or precious metals-related securities) such as stock, bonds or convertible bonds issued by REITs or companies that mine precious metals.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund may also purchase convertible securities.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;When choosing investments, Fund management considers various factors, including opportunities for equity or debt investments to increase in value, expected dividends and interest rates. The Fund generally seeks diversification across markets, industries and issuers as one of its strategies to reduce volatility. The Fund has no geographic limits on where it may invest. This flexibility allows Fund management to look for investments in markets around the world, including emerging markets, that it believes will provide the best asset allocation to meet the Fund&#x2019;s objective. The Fund may invest in the securities of companies of any market capitalization.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;Generally, the Fund may invest in the securities of corporate and governmental issuers located anywhere in the world. The Fund may emphasize foreign securities when Fund management expects these investments to outperform U.S. securities. When choosing investment markets, Fund management considers various factors, including economic and political conditions, potential for economic growth and possible changes in currency exchange rates. In addition to investing in foreign securities, the Fund actively manages its exposure to foreign currencies through the use of forward currency contracts and other currency derivatives. The Fund may own foreign cash equivalents or foreign bank deposits as part of the Fund&#x2019;s investment strategy. The Fund will also invest in non&#x2011;U.S. currencies. The Fund may underweight or overweight a currency based on the Fund management team&#x2019;s outlook.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;Under normal circumstances, the Fund will continue to allocate a substantial amount (approximately 40% or more &#x2014; unless market conditions are not deemed favorable by BlackRock, in which case the Fund would invest at least 30%) of its total assets in securities of (i)&#160;foreign government issuers, (ii)&#160;issuers organized or located outside the U.S., (iii) issuers which primarily trade in a market located outside the U.S., or (iv)&#160;issuers doing a substantial amount of business outside the U.S., which the Fund considers to be companies that derive at least 50% of their revenue or profits from business outside the U.S. or have at least 50% of their sales or assets outside the U.S. The Fund will allocate its assets among various regions and countries including the United States (but in no less than three different countries). For temporary defensive purposes the Fund may deviate very substantially from the allocation described above.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund may use derivatives, including options, futures, swaps (including, but not limited to, total return swaps that may be referred to as contracts for difference) and forward contracts both to seek to increase the return of the Fund and to hedge (or protect) the value of its assets against adverse movements in currency exchange rates, interest rates and movements in the securities markets. The Fund may invest in indexed securities and inverse securities.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund may seek to provide exposure to the investment returns of real assets that trade in the commodity markets through investment in commodity-linked derivative instruments and investment vehicles such as exchange-traded funds that invest exclusively in commodities and are designed to provide this exposure without direct investment in physical commodities. The Fund may also gain exposure to commodity markets by investing up to 25% of its total assets in BlackRock Cayman Global Allocation Portfolio I, Ltd. (the &#x201c;Subsidiary&#x201d;), a wholly owned subsidiary of the Fund formed in the Cayman Islands, which invests primarily in commodity-related instruments. The Subsidiary may also hold cash and invest in other instruments, including fixed income securities, either as investments or to serve as margin or collateral for the Subsidiary&#x2019;s derivative positions. The Subsidiary (unlike the Fund) may invest without limitation in commodity-related instruments. However, the Subsidiary is otherwise subject to the same fundamental, non&#x2011;fundamental and certain other investment restrictions as the Fund.&lt;/div&gt; </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_RiskLoseMoneyMember"
      id="t_109_b66bc7f2_8930_f2d0_7c81_0709f2d6885c">You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_EquitySecuritiesRiskMember"
      id="t_73_b3986ec6_7c31_0c0a_9cd2_e4c54d7510b6"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Equity Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Stock markets are volatile. The price of equity securities fluctuates based on changes in a company&#x2019;s financial condition and overall market and economic conditions.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_ForeignSecuritiesRiskMember"
      id="t_74_ed971c75_2251_86b4_490b_633891004165"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Foreign Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Foreign investments often involve special risks not present in U.S. investments that can increase the chances that the Fund will lose money. These risks include:&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;The Fund generally holds its foreign securities and cash in foreign banks and securities depositories, which may be recently organized or new to the foreign custody business and may be subject to only limited or no regulatory oversight.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;Changes in foreign currency exchange rates can affect the value of the Fund&#x2019;s portfolio.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;The economies of certain foreign markets may not compare favorably with the economy of the United States with respect to such issues as growth of gross national product, reinvestment of capital, resources and balance of payments position.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;The governments of certain countries, or the U.S. Government with respect to certain countries, may prohibit or impose substantial restrictions through capital controls and/or sanctions on foreign investments in the capital markets or certain industries in those countries, which may prohibit or restrict the ability to own or transfer currency, securities, derivatives or other assets.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to the same extent as does the United States and may not have laws to protect investors that are comparable to U.S. securities laws.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;Settlement and clearance procedures in certain foreign markets may result in delays in payment for or delivery of securities not typically associated with settlement and clearance of U.S. investments.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;The Fund&#x2019;s claims to recover foreign withholding taxes may not be successful, and if the likelihood of recovery of foreign withholding taxes materially decreases, due to, for example, a change in tax regulation or approach in the foreign country, accruals in the Fund&#x2019;s net asset value for such refunds may be written down partially or in full, which will adversely affect the Fund&#x2019;s net asset value.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_DebtSecuritiesRiskMember"
      id="t_75_bed7eddc_d949_440d_480d_07ec808332dc"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Debt Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Debt securities, such as bonds, involve risks, such as credit risk, interest rate risk, extension risk, and prepayment risk, each of which are described in further detail below:&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Credit Risk &#x2014; &lt;/span&gt;Credit risk refers to the possibility that the issuer of a debt security (i.e., the borrower) will not be able to make payments of interest and principal when due. Changes in an issuer&#x2019;s credit rating or the market&#x2019;s perception of an issuer&#x2019;s creditworthiness may also affect the value of the Fund&#x2019;s investment in that issuer. The degree of credit risk depends on both the financial condition of the issuer and the terms of the obligation.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Interest Rate Risk&lt;/span&gt; &#x2014; The market value of bonds and other fixed-income securities changes in response to interest rate changes and other factors. Interest rate risk is the risk that prices of bonds and other fixed-income securities will increase as interest rates fall and decrease as interest rates rise.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;The Fund may be subject to a greater risk of rising interest rates during a period of historically low interest rates. For example, if interest rates increase by 1%, assuming a current portfolio duration of ten years, and all other factors being equal, the value of the Fund&#x2019;s investments would be expected to decrease by 10%. (Duration is a measure of the price sensitivity of a debt security or portfolio of debt securities to relative changes in interest rates.) The magnitude of these fluctuations in the market price of bonds and other fixed-income securities is generally greater for those securities with longer maturities. Fluctuations in the market price of the Fund&#x2019;s investments will not affect interest income derived from instruments already owned by the Fund, but will be reflected in the Fund&#x2019;s net asset value. The Fund may lose money if short-term or long-term interest rates rise sharply in a manner not anticipated by Fund management.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;To the extent the Fund invests in debt securities that may be prepaid at the option of the obligor (such as mortgage-backed securities), the sensitivity of such securities to changes in interest rates may increase (to the detriment of the Fund) when interest rates rise. Moreover, because rates on certain floating rate debt securities typically reset only periodically, changes in prevailing interest rates (and particularly sudden and significant changes) can be expected to cause some fluctuations in the net asset value of the Fund to the extent that it invests in floating rate debt securities.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;These basic principles of bond prices also apply to U.S. Government securities. A security backed by the &#x201c;full faith and credit&#x201d; of the U.S. Government is guaranteed only as to its stated interest rate and face value at maturity, not&lt;/div&gt;  &lt;div style="margin-top: 0pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;its current market price. Just like other fixed-income securities, government-guaranteed securities will fluctuate in value when interest rates change.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;A general rise in interest rates has the potential to cause investors to move out of fixed-income securities on a large scale, which may increase redemptions from funds that hold large amounts of fixed-income securities. Heavy redemptions could cause the Fund to sell assets at inopportune times or at a loss or depressed value and could hurt the Fund&#x2019;s performance.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Extension Risk&lt;/span&gt; &#x2014; When interest rates rise, certain obligations will be paid off by the obligor more slowly than anticipated, causing the value of these obligations to fall.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Prepayment Risk&lt;/span&gt; &#x2014; When interest rates fall, certain obligations will be paid off by the obligor more quickly than originally anticipated, and the Fund may have to invest the proceeds in securities with lower yields.&lt;/div&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_CommoditiesRelatedInvestmentsRiskMember"
      id="t_76_a7215dfa_50fa_c3fc_f1c6_f32bce9bbd77"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Commodities Related Investments Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Exposure to the commodities markets may subject the Fund to greater volatility than investments in traditional securities. The value of commodity-linked derivative investments may be affected by changes in overall market movements, commodity index volatility, changes in inflation, interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, embargoes, tariffs and international economic, political and regulatory developments.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_ConvertibleSecuritiesRiskMember"
      id="t_77_d60401a0_f0d5_5016_bff5_93b88de69369"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Convertible Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The market value of a convertible security performs like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest, principal or dividends when due, and their market value may change based on changes in the issuer&#x2019;s credit rating or the market&#x2019;s perception of the issuer&#x2019;s creditworthiness. Since it derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock, including the potential for increased volatility in the price of the convertible security.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_CorporateLoansRiskMember"
      id="t_78_dde24fbc_0e47_0a4e_e351_f236675d5b0f"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Corporate Loans Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Commercial banks and other financial institutions or institutional investors make corporate loans to companies that need capital to grow or restructure. Borrowers generally pay interest on corporate loans at rates that change in response to changes in market interest rates such as the Secured Overnight Financing Rate (&#x201c;SOFR&#x201d;) or the prime rates of U.S. banks. As a result, the value of corporate loan investments is generally less exposed to the adverse effects of shifts in market interest rates than investments that pay a fixed rate of interest. The market for corporate loans may be subject to irregular trading activity and wide bid/ask spreads. In addition, transactions in corporate loans may settle on a delayed basis. As a result, the proceeds from the sale of corporate loans may not be readily available to make additional investments or to meet the Fund&#x2019;s redemption obligations. To the extent the extended settlement process gives rise to short-term liquidity needs, the Fund may hold additional cash, sell investments or temporarily borrow from banks and other lenders.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_DerivativesRisksMember"
      id="t_79_b250c605_7d57_229f_31b6_caf05ec508a8"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Derivatives Risk &lt;/span&gt;&lt;/span&gt;&#x2014; The Fund&#x2019;s use of derivatives may increase its costs, reduce the Fund&#x2019;s returns and/or increase volatility. Derivatives involve significant risks, including:&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Leverage Risk &lt;/span&gt;&#x2014; The Fund&#x2019;s use of derivatives can magnify the Fund&#x2019;s gains and losses. Relatively small market movements may result in large changes in the value of a derivatives position and can result in losses that greatly exceed the amount originally invested.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Market Risk&lt;/span&gt; &#x2014; Some derivatives are more sensitive to interest rate changes and market price fluctuations than other securities. The Fund could also suffer losses related to its derivatives positions as a result of unanticipated market movements, which losses are potentially unlimited. Finally, BlackRock may not be able to predict correctly the direction of securities prices, interest rates and other economic factors, which could cause the Fund&#x2019;s derivatives positions to lose value.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Counterparty Risk&lt;/span&gt; &#x2014; Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will be unable or unwilling to fulfill its contractual obligation, and the related risks of having concentrated exposure to such a counterparty.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Illiquidity Risk&lt;/span&gt; &#x2014; The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Operational Risk&lt;/span&gt; &#x2014; The use of derivatives includes the risk of potential operational issues, including documentation issues, settlement issues, systems failures, inadequate controls and human error.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Legal Risk&lt;/span&gt; &#x2014; The risk of insufficient documentation, insufficient capacity or authority of counterparty, or legality or enforceability of a contract.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Volatility and Correlation Risk&lt;/span&gt; &#x2014; Volatility is defined as the characteristic of a security, an index or a market to fluctuate significantly in price within a short time period. A risk of the Fund&#x2019;s use of derivatives is that the fluctuations in their values may not correlate with the overall securities markets.&lt;/div&gt;  &lt;div style="margin-top: 0pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Valuation Risk &lt;/span&gt;&#x2014; Valuation for derivatives may not be readily available in the market. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Hedging Risk&lt;/span&gt; &#x2014; Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Fund&#x2019;s hedging transactions will be effective. The use of hedging may result in certain adverse tax consequences.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; margin-left: 3%; font-size: 10pt; font-family: arial;"&gt;&lt;span style="font-style: italic;"&gt;Tax Risk &lt;/span&gt;&#x2014; Certain aspects of the tax treatment of derivative instruments, including swap agreements and commodity-linked derivative instruments, are currently unclear and may be affected by changes in legislation, regulations or other legally binding authority. Such treatment may be less favorable than that given to a direct investment in an underlying asset and may adversely affect the timing, character and amount of income the Fund realizes from its investments.&lt;/div&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_DistressedSecuritiesRiskMember"
      id="t_80_8114cd82_ffe2_490f_e653_59bb77c69eaa"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Distressed Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Distressed securities are speculative and involve substantial risks in addition to the risks of investing in junk bonds. The Fund will generally not receive interest payments on the distressed securities and may incur costs to protect its investment. In addition, distressed securities involve the substantial risk that principal will not be repaid. These securities may present a substantial risk of default or may be in default at the time of investment. The Fund may incur additional expenses to the extent it is required to seek recovery upon a default in the payment of principal of or interest on its portfolio holdings. In any reorganization or liquidation proceeding relating to a portfolio company, the Fund may lose its entire investment or may be required to accept cash or securities with a value less than its original investment. Distressed securities and any securities received in an exchange for such securities may be subject to restrictions on resale.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_EmergingMarketsRiskMember"
      id="t_81_8056842b_7e94_3b30_1ede_a5e3c06c1f8b"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Emerging Markets Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Emerging markets are riskier than more developed markets because they tend to develop unevenly and may never fully develop. Investments in emerging markets may be considered speculative. Emerging markets are more likely to experience hyperinflation and currency devaluations, which adversely affect returns to U.S. investors. In addition, many emerging financial markets have far lower trading volumes and less liquidity than developed markets.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_HighPortfolioTurnoverRiskMember"
      id="t_82_53b1c1d1_5c9f_f4d8_f4f0_3bbb603c526f"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;High Portfolio Turnover Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The Fund may engage in active and frequent trading of its portfolio securities. High portfolio turnover (more than 100%) may result in increased transaction costs to the Fund, including brokerage commissions, dealer mark&#x2011;ups and other transaction costs on the sale of the securities and on reinvestment in other securities. The sale of Fund portfolio securities may result in the realization and/or distribution to shareholders of higher capital gains or losses as compared to a fund with less active trading policies. These effects of higher than normal portfolio turnover may adversely affect Fund performance.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_HighYieldBondsRiskMember"
      id="t_83_4f168e40_a52c_d729_6496_139d86d0d009"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;/span&gt;&lt;span style="font-style: italic;"&gt;&lt;/span&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;High Yield Bonds Risk&lt;/span&gt;&lt;/span&gt;&lt;span style="font-style: italic;"&gt;&lt;/span&gt;&lt;span style="font-weight: bold;"&gt;&lt;/span&gt; &#x2014; Although junk bonds generally pay higher rates of interest than investment grade bonds, junk bonds are high risk investments that are considered speculative and may cause income and principal losses for the Fund.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_IndexedAndInverseSecuritiesRiskMember"
      id="t_84_c9f61c1b_364c_4e0c_0e1c_ecbce4c69c43"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Indexed and Inverse Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Indexed and inverse securities provide a potential return based on a particular index of value or interest rates. The Fund&#x2019;s return on these securities will be subject to risk with respect to the value of the particular index. These securities are subject to leverage risk and correlation risk. Certain indexed and inverse securities have greater sensitivity to changes in interest rates or index levels than other securities, and the Fund&#x2019;s investment in such instruments may decline significantly in value if interest rates or index levels move in a way Fund management does not anticipate.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_LeverageRiskMember"
      id="t_86_19f12091_cccc_bde7_79ee_6ca9374af470"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Leverage Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Some transactions may give rise to a form of economic leverage. These transactions may include, among others, derivatives, and may expose the Fund to greater risk and increase its costs. The use of leverage may cause the Fund to liquidate portfolio positions when it may not be advantageous to do so to satisfy its obligations or to meet the applicable requirements of the Investment Company Act of 1940, as amended (the &#x201c;Investment Company Act&#x201d;), and the rules thereunder. Increases and decreases in the value of the Fund&#x2019;s portfolio will be magnified when the Fund uses leverage.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_MarketRiskAndSelectionRiskMember"
      id="t_87_e7ea424c_d8e6_8695_6728_bfc45691243f"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Market Risk and Selection Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a security or other asset may decline due to changes in general market conditions, economic trends or events that are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class.&#160;Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its investments. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;  
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 3%;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top;"&gt;&lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_MidCapSecuritiesRiskMember"
      id="t_88_32222663_6aec_93ea_3584_b2199e8e966b"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Mid Cap Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The securities of mid cap companies generally trade in lower volumes and are generally subject to greater and less predictable price changes than the securities of larger capitalization companies.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_MortgageAndAssetBackedSecuritiesRisksMember"
      id="t_89_04ae21c1_5e2f_6834_27e7_a01412d9b76b"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Mortgage- and Asset-Backed Securities Risks&lt;/span&gt;&lt;/span&gt; &#x2014; Mortgage- and asset-backed securities represent interests in &#x201c;pools&#x201d; of mortgages or other assets, including consumer loans or receivables held in trust. Mortgage- and asset-backed securities are subject to credit, interest rate, prepayment and extension risks. These securities also are subject to risk of default on the underlying mortgage or asset, particularly during periods of economic downturn. Small movements in interest rates (both increases and decreases) may quickly and significantly reduce the value of certain mortgage-backed securities.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_OperationalAndTechnologyRisksMember"
      id="t_90_1f75ce72_ad5b_1316_6912_7644a2d95491"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Operational and Technology Risks&lt;/span&gt;&lt;/span&gt; &#x2014; The Fund is directly and indirectly susceptible to operational and technology risks, including those related to human errors, processing errors, communication errors, systems failures, cybersecurity incidents, and the use of artificial intelligence and machine learning (&#x201c;AI&#x201d;), which may result in losses for the Fund and its shareholders or may impair the Fund&#x2019;s operations. While the Fund&#x2019;s service providers are required to have appropriate operational, information security and cybersecurity risk management policies and procedures, their methods of risk management may differ from those of the Fund. Operational and technology risks for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and may cause the Fund&#x2019;s investments in such issuers to lose value.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_PreciousMetalAndRelatedSecuritiesRiskMember"
      id="t_91_3ee39096_489e_4e37_6a85_41e06907e9df"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Precious Metal and Related Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Prices of precious metals and of precious metal related securities historically have been very volatile. The high volatility of precious metal prices may adversely affect the financial condition of companies involved with precious metals. The production and sale of precious metals by governments or central banks or other larger holders can be affected by various economic, financial, social and political factors, which may be unpredictable and may have a significant impact on the prices of precious metals. Other factors that may affect the prices of precious metals and securities related to them include changes in inflation, the outlook for inflation and changes in industrial and commercial demand for precious metals.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_PreferredSecuritiesRiskMember"
      id="t_92_1043fa23_16c6_b17b_4e52_5ed8717b60e0"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Preferred Securities Risk &lt;/span&gt;&lt;/span&gt;&#x2014; Preferred securities may pay fixed or adjustable rates of return. Preferred securities are&#160;subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company&#x2019;s preferred securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company&#x2019;s financial condition or prospects. Preferred securities of smaller companies may be more vulnerable to adverse developments than preferred securities of larger companies.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_RealEstateRelatedSecuritiesRiskMember"
      id="t_93_524e958c_e9f1_7113_e772_b75a55261e71"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Real Estate-Related Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The main risk of real estate-related securities is that the value of the underlying real estate may go down. Many factors may affect real estate values. These factors include both the general and local economies, vacancy rates, changes in rent schedules, tenant bankruptcies, the ability to re&#x2011;lease space under expiring leases&#160;on attractive terms, the amount of new construction in a particular area, the laws and regulations (including zoning, environmental and tax laws) affecting real estate and the costs of owning, maintaining and improving real estate. The availability of mortgage financing and changes in interest rates may also affect real estate values. If the&#160;Fund&#x2019;s real estate-related investments are concentrated in one geographic area or in one property type, the Fund will be particularly subject to the risks associated with that area or property type. Many issuers of real estate&#x2011;related securities are highly leveraged, which increases the risk to holders of such securities. The value of the securities the Fund buys will not necessarily track the value of the underlying investments of the issuers of such&#160;securities. In addition, certain issuers of real estate-related securities may have developed or commenced development on properties and may develop additional properties in the future. Real estate development involves significant risks in addition to those involved in the ownership and operation of established properties. Real estate securities may have limited diversification and are, therefore, subject to risks inherent in operating and financing a limited number of projects. Real estate securities are also subject to heavy cash flow dependency and defaults by borrowers or tenants.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_REITInvestmentRiskMember"
      id="t_94_71412913_972f_b905_dad5_5ef4b5b5e068"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;REIT Investment Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Investments in REITs involve unique risks. REITs may have limited financial resources, may trade less frequently and in limited volume, may engage in dilutive offerings of securities and may be more volatile than other securities. REIT issuers may also fail to maintain their exemptions from investment company registration or fail to qualify for the &#x201c;dividends paid deduction&#x201d; under the Internal Revenue Code of 1986, as amended, which allows REITs to reduce their corporate taxable income for dividends paid to their shareholders.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_RightsRiskMember"
      id="t_95_00c8dd44_7f95_99b1_844b_e6b59e64e08f"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Rights Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The failure to exercise subscription rights to purchase common stock would result in the dilution of the Fund&#x2019;s interest in the issuing company. The market for such rights is not well developed, and, accordingly, the Fund may not always realize full value on the sale of rights.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_RiskOfInvestingInTheUnitedStatesMember"
      id="t_96_4729f8a9_a6a1_31f9_cc7f_8df016a2666e"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Risk of Investing in the United States&lt;/span&gt;&lt;/span&gt; &#x2014; Certain changes in the U.S. economy, such as when the U.S. economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_RisksOfLoanAssignmentsAndParticipationsMember"
      id="t_97_fd425d2b_2fd4_adfa_bc7c_a24151060f00"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Risks of Loan Assignments and Participations&lt;/span&gt;&lt;/span&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt; &lt;/span&gt;&lt;/span&gt;&#x2014; As the purchaser of an assignment, the Fund typically succeeds to all the rights and obligations of the assigning institution and becomes a lender under the credit agreement with respect to the debt obligation; however, the Fund may not be able unilaterally to enforce all rights and remedies under the loan and with regard to any associated collateral. Because assignments may be arranged through private negotiations between potential assignees and potential assignors, the rights and obligations acquired by the Fund as the purchaser of an assignment may differ from, and be more limited than, those held by the assigning lender. In addition, if the loan is foreclosed, the Fund could become part owner of any collateral and could bear the costs and liabilities of owning and disposing of the collateral. The Fund may be required to pass along to a purchaser that buys a loan from the Fund by way of assignment a portion of any fees to which the Fund is entitled under the loan. In connection with purchasing participations, the Fund generally will have no right to enforce compliance by the borrower with the terms of the loan agreement relating to the loan, nor any rights of set-off against the borrower, and the Fund may not directly benefit from any collateral supporting the loan in which it has purchased the participation. As a result, the Fund will be subject to the credit risk of both the borrower and the lender that is selling the participation. In the event of the insolvency of the lender selling a participation, the Fund may be treated as a general creditor of the lender and may not benefit from any set-off between the lender and the borrower.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_SmallCapAndEmergingGrowthSecuritiesRiskMember"
      id="t_98_940b2729_6b1e_be84_4c0e_6ab234b128e7"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Small Cap and Emerging Growth Securities Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Small cap or emerging growth companies may have limited product lines or markets. They may be less financially secure than larger, more established companies. They may depend on a more limited management group than larger capitalized companies.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_SovereignDebtRiskMember"
      id="t_99_a71b1d40_d7d6_2644_e038_17fe1b4450d0"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Sovereign Debt Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Sovereign debt instruments are subject to the risk that a governmental entity may delay or refuse to pay interest or repay principal on its sovereign debt, due, for example, to cash flow problems, insufficient foreign currency reserves, political considerations, the relative size of the governmental entity&#x2019;s debt position in relation to the economy or the failure to put in place economic reforms required by the International Monetary Fund or other multilateral agencies.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_StructuredNotesRiskMember"
      id="t_100_3ca7df6e_0475_ca0a_d9ff_3def437e8d4b"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Structured Notes Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Structured notes and other related instruments purchased by the Fund are generally privately negotiated debt obligations where the principal and/or interest is determined by reference to the performance of a specific asset, benchmark asset, market or interest rate (&#x201c;reference measure&#x201d;). The purchase of structured notes exposes the Fund to the credit risk of the issuer of the structured product. Structured notes may be leveraged, increasing the volatility of each structured note&#x2019;s value relative to the change in the reference measure. Structured notes may also be less liquid and more difficult to price accurately than less complex securities and instruments or more traditional debt securities.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_SubsidiaryRiskMember"
      id="t_101_01fc21c1_30c9_5dc2_2358_5e4f3d741c96"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Subsidiary Risk&lt;/span&gt;&lt;/span&gt; &#x2014; By investing in the Subsidiary, the Fund is indirectly exposed to the risks associated with the Subsidiary&#x2019;s investments. The commodity-related instruments held by the Subsidiary are generally similar to those that are permitted to be held by the Fund and are subject to the same risks that apply to similar investments if held directly by the Fund (see &#x201c;Commodities Related Investments Risk&#x201d; above). There can be no assurance that the investment objective of the Subsidiary will be achieved. The Subsidiary is not registered under the Investment Company Act, and, unless otherwise noted in this prospectus, is not subject to all the investor protections of the Investment Company Act. However, the Fund wholly owns and controls the Subsidiary, and the Fund and the Subsidiary are both managed by BlackRock, making it unlikely that the Subsidiary will take action contrary to the interests of the Fund and its shareholders. The Board has oversight responsibility for the investment activities of the Fund, including its investment in the Subsidiary, and the Fund&#x2019;s role as sole shareholder of the Subsidiary. The Subsidiary is subject to the same investment restrictions and limitations, and follows the same compliance policies and procedures, as the Fund, except that the Subsidiary may invest without limitation in commodity-related instruments. Changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Fund and/or the Subsidiary to operate as described in this prospectus and the Statement of Additional Information and could adversely affect the Fund.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003866Member_WarrantsRiskMember"
      id="t_102_c22ae37d_f999_ffea_2e85_a9eae4ea23dc"> 
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Warrants Risk&lt;/span&gt;&lt;/span&gt; &#x2014; If the price of the underlying stock does not rise above the exercise price before the warrant expires, the warrant generally expires without any value and the Fund will lose any amount it paid for the warrant. Thus, investments in warrants may involve substantially more risk than investments in common stock. Warrants may trade in the same markets as their underlying stock; however, the price of the warrant does not necessarily move with the price of the underlying stock.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="S000003866Member"
      id="t_114_4b38822c_56eb_7a54_c3be_cef70863c1f8">Performance Information</oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="S000003866Member"
      id="t_72_bd65cbc0_5b94_4e42_9595_ff885ed3d58f"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The information shows you how the Fund&#x2019;s performance has varied year by year and provides some indication of the risks of investing in the Fund. The table compares the Fund&#x2019;s performance to that of the FTSE World Index and the Reference Benchmark, which is comprised of the returns of the S&amp;amp;P 500&lt;sup style="font-size: 75%; vertical-align: top;"&gt;&#xae;&lt;/sup&gt; Index (36%), the FTSE World (ex U.S.) Index (24%), the ICE BofA Current 5-Year U.S. Treasury Index (24%), and the FTSE Non-U.S. Dollar World Government Bond Index (16%). The Reference Benchmark is relevant to the Fund because it has characteristics similar to the Fund&#x2019;s investment strategies. To the extent that dividends and distributions have been paid by the Fund, the performance information for the Fund in the chart and table assumes reinvestment of the dividends and distributions. As with all such investments, past performance is not an indication of future results. The bar chart and table do not reflect separate account fees and expenses. If they did, returns would be less than those shown. If the Fund&#x2019;s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund&#x2019;s returns would have been lower.&lt;/div&gt; </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="S000003866Member"
      id="t_110_709df19c_7125_351d_a3f8_b3cc69e98da1">The information shows you how the Fund&#x2019;s performance has varied year by year and provides some indication of the risks of investing in the Fund.</oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformanceAdditionalMarketIndex
      contextRef="S000003866Member"
      id="t_111_09019a2e_cdb5_3e24_15e1_7a95636aab06">The table compares the Fund&#x2019;s performance to that of the FTSE World Index and the Reference Benchmark, which is comprised of the returns of the S&amp;P 500&#xae; Index (36%), the FTSE World (ex U.S.) Index (24%), the ICE BofA Current 5-Year U.S. Treasury Index (24%), and the FTSE Non-U.S. Dollar World Government Bond Index (16%). The Reference Benchmark is relevant to the Fund because it has characteristics similar to the Fund&#x2019;s investment strategies.</oef:PerformanceAdditionalMarketIndex>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="S000003866Member"
      id="t_112_89482c95_9ee0_f6cd_2096_e9ca30ec152f">As with all such investments, past performance is not an indication of future results.</oef:PerformancePastDoesNotIndicateFuture>
    <oef:BarChartDoesNotReflectSalesLoads
      contextRef="S000003866Member"
      id="t_113_110bf418_260a_f570_91e8_268045119039">The bar chart and table do not reflect separate account fees and expenses. If they did, returns would be less than those shown.</oef:BarChartDoesNotReflectSalesLoads>
    <oef:BarChartHeading
      contextRef="S000003866Member"
      id="t_115_15a0a7ea_6c5c_e3ae_7bd2_c26ba086278a"> ANNUAL TOTAL RETURNS  BlackRock Global Allocation Portfolio  As of 12/31 </oef:BarChartHeading>
    <oef:BarChartClosingTextBlock
      contextRef="S000003866Member"
      id="t_120_83dca882_6802_7f61_d558_06f47d233fd9"> &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;During the ten&#x2011;year period shown in the bar chart, the highest return for a quarter was 14.66% (quarter ended June 30, 2020) and the lowest return for a quarter was -12.35% (quarter ended March 31, 2020).&lt;/div&gt; </oef:BarChartClosingTextBlock>
    <oef:HighestQuarterlyReturnLabel
      contextRef="S000003866Member_C000010832Member"
      id="t_116_40ae37f8_bcfd_dad4_b680_5e4afa468fab">highest return</oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="S000003866Member_C000010832Member"
      decimals="4"
      id="h_64_e922b222_a475_015f_b280_fd5b39303d60"
      unitRef="pure">0.1466</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="S000003866Member_C000010832Member"
      id="t_117_edebd70c_dbc7_359f_281c_5049d76cff0f">2020-06-30</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="S000003866Member_C000010832Member"
      id="t_118_7d77a946_aff3_5a11_5565_3e93e832006d">lowest return</oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="S000003866Member_C000010832Member"
      decimals="4"
      id="h_65_0896a8cb_bc6f_3f64_e3f5_b62499720c74"
      unitRef="pure">-0.1235</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="S000003866Member_C000010832Member"
      id="t_119_86f042e7_93fd_a12d_c8c2_be6988a96372">2020-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:PerformanceTableHeading
      contextRef="S000003866Member"
      id="t_121_2109f5b5_a7fc_fe1a_8e4e_07bbfd55dbde">For the periods ended 12/31/25Average Annual Total Returns</oef:PerformanceTableHeading>
    <oef:AvgAnnlRtrPct
      contextRef="FY2025_C000010832Member"
      decimals="4"
      id="h_66_7277c720_677f_8f73_9d07_06f8a055160b"
      unitRef="pure">0.1961</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FiveY2025_C000010832Member"
      decimals="4"
      id="h_69_03e037dc_6100_3c16_38f0_199f413c8826"
      unitRef="pure">0.0598</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="TenY2025_C000010832Member"
      decimals="4"
      id="h_72_3fc2e696_14ae_caf9_b8df_df360671dff2"
      unitRef="pure">0.0773</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FY2025_FTSEWorldIndexMember"
      decimals="4"
      id="h_67_88a03733_3c48_442e_c105_35b5c334d0c2"
      unitRef="pure">0.2348</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FiveY2025_FTSEWorldIndexMember"
      decimals="4"
      id="h_70_0b06e200_f4d5_0bc4_e00d_9509d35e447f"
      unitRef="pure">0.1252</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="TenY2025_FTSEWorldIndexMember"
      decimals="4"
      id="h_73_44cde936_fc98_4aea_77ce_b01a2e48600a"
      unitRef="pure">0.1267</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FY2025_ReferenceBenchmarkMember"
      decimals="4"
      id="h_68_25c07e90_8390_54fb_797b_2fbba17941ab"
      unitRef="pure">0.1778</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="FiveY2025_ReferenceBenchmarkMember"
      decimals="4"
      id="h_71_94ec86f5_9f6c_d161_b40f_0049259acd1a"
      unitRef="pure">0.0668</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="TenY2025_ReferenceBenchmarkMember"
      decimals="4"
      id="h_74_1544ac4a_1e0a_9c56_36b2_cccee8ed13f7"
      unitRef="pure">0.0809</oef:AvgAnnlRtrPct>
    <oef:RiskReturnHeading
      contextRef="S000003870Member"
      id="t_92_0a73a8db_d10a_6753_8f98_31bfae05744e"> Fund Overview  Key Facts About BlackRock Government Money Market Portfolio </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="S000003870Member"
      id="t_76_de27a4b0_ec29_4fc5_ae18_18c053b2c7a5"> Investment Objective  </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="S000003870Member"
      id="t_77_483513cf_c467_47da_b1d1_0bdd0387e156"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The investment objective of the BlackRock Government Money Market Portfolio (the &#x201c;Government Money Market Portfolio&#x201d; or the &#x201c;Fund&#x201d;), a series of BlackRock Series Fund, Inc. (the &#x201c;Corporation&#x201d;), is to seek to preserve capital, to maintain liquidity and achieve the highest possible current income consistent with the foregoing.&lt;/div&gt; </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="S000003870Member"
      id="t_78_283fdc9b_b5c9_4aa9_ac02_a6ed6487f11a"> Fees and Expenses of the Fund  </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="S000003870Member"
      id="t_79_736dd1bf_23ee_4f33_89ec_ae5f1512a967"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. &lt;span style="font-weight: bold;"&gt;The table and example below do not include separate account fees and expenses, and expenses would be higher if these fees and expenses were included.&lt;/span&gt; Please refer to your variable annuity or insurance contract (the &#x201c;Contract&#x201d;) prospectus for information on the separate account fees and expenses associated with your Contract.&lt;/div&gt; </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="S000003870Member"
      id="t_93_acdeab16_c722_41f1_b633_f2b57dcaf4f6"> Shareholder Fees (fees paid directly from your investment)  The Fund is not subject to any Shareholder Fees. </oef:ShareholderFeesCaption>
    <oef:OperatingExpensesCaption
      contextRef="S000003870Member"
      id="t_81_0ee6167b_c83e_4f1f_b44b_551557decedf"> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="S000003870Member_C000010836Member"
      decimals="4"
      id="h_64_e29e1fd1_8189_49ca_b01d_85fca07b5a45"
      unitRef="pure">0.0037</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="S000003870Member_C000010836Member"
      decimals="4"
      id="h_65_7a8dc767_a31d_41df_9942_17dd011ce134"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="S000003870Member_C000010836Member"
      decimals="4"
      id="h_66_7988fba3_14d2_4ac9_9dab_67e82798af74"
      unitRef="pure">0.0024</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="S000003870Member_C000010836Member"
      decimals="4"
      id="h_67_9b8e6832_70f2_4de8_a611_cb7bcbbc2cdb"
      unitRef="pure">0.0061</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="S000003870Member_C000010836Member"
      decimals="4"
      id="h_68_15c7b3ac_b013_42f5_a5b2_b56fa8bcdffa"
      unitRef="pure">-0.0018</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="S000003870Member_C000010836Member"
      decimals="4"
      id="h_69_e2c2de8f_3add_4491_9501_01014a66b8b4"
      unitRef="pure">0.0043</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="S000003870Member"
      id="t_94_a04504df_c0ec_cfdb_8109_700d72745b90">June&#160;30, 2027</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpenseExampleHeading
      contextRef="S000003870Member"
      id="t_82_8161fcd6_dc3c_4226_89ba_4bb0ed34e192"> Example: </oef:ExpenseExampleHeading>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="S000003870Member"
      id="t_83_b161742a_fd8c_4ecf_8a1f_b645ac89f1b6"> &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund&#x2019;s operating expenses remain the same. The Example does not reflect charges imposed by the Contract. See the Contract prospectus for information on such charges. Although your actual costs may be higher or lower, based on these assumptions your costs would be:&lt;/div&gt; </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="S000003870Member_C000010836Member"
      decimals="INF"
      id="h_70_3bda1df9_b094_4eab_a165_f8ff578ff9fa"
      unitRef="USD">44</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="S000003870Member_C000010836Member"
      decimals="INF"
      id="h_71_dda9523b_3495_4179_a51d_33a1d1d1653a"
      unitRef="USD">177</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="S000003870Member_C000010836Member"
      decimals="INF"
      id="h_72_56e1850c_8579_4878_ba54_5b3f135b9746"
      unitRef="USD">322</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="S000003870Member_C000010836Member"
      decimals="INF"
      id="h_73_841f034d_a5b1_458f_b4cd_a6b1a7b8d44e"
      unitRef="USD">745</oef:ExpenseExampleYear10>
    <oef:StrategyHeading
      contextRef="S000003870Member"
      id="t_84_beb897e1_4ac8_4a5a_bf76_435161291faa"> Principal Investment Strategies of the Fund  </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="S000003870Member"
      id="t_85_ca54cc0e_ec24_4d2f_afee_b6b6553c2aae"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund invests at least 99.5% of its total assets in cash, U.S. Treasury bills, notes and other obligations issued or guaranteed as to principal and interest by the U.S. Government, its agencies or instrumentalities, and repurchase agreements secured by such obligations or cash. The Fund invests in securities maturing in 397 days or less (with certain exceptions) and the portfolio will have a dollar-weighted average maturity of 60 days or less and a dollar-weighted average life of 120 days or less. The Fund may invest in variable and floating rate instruments, and transact in securities on a when-issued, delayed delivery or forward commitment basis.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The Fund will invest, under normal circumstances, at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in U.S. Treasury bills, notes and other obligations issued or guaranteed as to principal and interest by the U.S. Government, its agencies or instrumentalities, and repurchase agreements secured by such&lt;/div&gt;  &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;obligations. This policy is a non&#x2011;fundamental policy of the Fund, and the Fund will not change the policy without providing shareholders with at least 60 days&#x2019; prior notice of any change in the policy.&lt;/div&gt;  &lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The securities purchased by the Fund are subject to the quality, diversification, and other requirements of Rule&#160;2a&#x2011;7 under the Investment Company Act of 1940, as amended (the &#x201c;Investment Company Act&#x201d;), and other rules of the Securities and Exchange Commission.&lt;/div&gt; </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003870Member_RiskLoseMoneyMember"
      id="t_95_31801652_30c3_bcca_9dec_4e80f37d722e">You could lose money by investing in the Fund.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003870Member_RiskMoneyMarketFundMayNotPreserveDollarMember"
      id="t_112_6be8e7f6_9758_d346_28af_b84da221d10d">Although the Fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003870Member_RiskNotInsuredDepositoryInstitutionMember"
      id="t_113_7830c9a4_9370_9e8c_a8cf_a89472991ec0">An investment in the Fund is not a bank account and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003870Member_RiskMoneyMarketFundSponsorMayNotProvideSupportMember"
      id="t_114_4ab51a03_8e85_cdc8_001e_20d9113ababa">The Fund&#x2019;s sponsor is not required to reimburse the Fund for losses, and you should not expect that the sponsor will provide financial support to the Fund at any time, including during periods of market stress.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="D20251231_20251231_S000003870Member_InterestRateRiskMember"
      id="t_115_448e5848_5072_750a_1769_f597733a702e">
&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Interest Rate Risk &lt;/span&gt;&lt;/span&gt;&#x2014;&#160;Interest rate risk is the risk that the value of a debt security may fall when interest rates rise. In general, the market price of debt securities with longer maturities will go up or down more in response to changes in interest rates than the market price of shorter-term securities. Due to fluctuations in interest rates, the market value of such securities may vary during the period shareholders own shares of the Fund. Very low or negative interest rates may magnify interest rate risk. During periods of very low or negative interest rates, the Fund may be unable to maintain positive returns or pay dividends to Fund shareholders. The Fund may be subject to a greater risk of rising interest rates during a period of historically low interest rates. Changing interest rates may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Fund&#x2019;s ability to achieve its investment objective.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
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&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Treasury Obligations Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Direct obligations of the U.S. Treasury have historically involved little risk of loss of principal if held to maturity. However, due to fluctuations in interest rates, the market value of such securities may vary during the period shareholders own shares of the Fund. In addition, notwithstanding that U.S. Treasury obligations are backed by the full faith and credit of the United States, circumstances could arise that could prevent the timely payment of interest or principal, such as reaching the legislative &#x201c;debt ceiling.&#x201d; Such non-payment could result in losses to the Fund and substantial negative consequences for the U.S. economy and the global financial system.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
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&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;U.S. Government Obligations Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Certain securities in which the Fund may invest, including securities issued by certain U.S. Government agencies and U.S. Government sponsored enterprises, are not guaranteed by the U.S.&#160;Government or supported by the full faith and credit of the United States. In addition, circumstances could arise that could prevent the timely payment of interest or principal on U.S. Government obligations, such as reaching the legislative &#x201c;debt ceiling.&#x201d; Such non-payment could result in losses to the Fund and substantial negative consequences for the U.S. economy and the global financial system.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
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&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Repurchase Agreements Risk&lt;/span&gt;&lt;/span&gt; &#x2014; If the other party to a repurchase agreement defaults on its obligation under the agreement, the Fund may suffer delays and incur costs or lose money in exercising its rights under the agreement. If the seller fails to repurchase the security and the market value of the security declines, the Fund may lose money.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
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&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Credit Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Credit risk refers to the possibility that the issuer of a debt security (&lt;span style="font-style: italic;"&gt;i.e.&lt;/span&gt;, the borrower) will be unable or unwilling to make timely payments of interest and principal when due or otherwise honor their obligations. Changes in an issuer&#x2019;s credit rating or the market&#x2019;s perception of an issuer&#x2019;s creditworthiness may also affect the value of the Fund&#x2019;s investment in that issuer.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
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&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Income Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Income risk is the risk that the Fund&#x2019;s yield will vary as short-term securities in its portfolio mature and the proceeds are reinvested in securities with different interest rates.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
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&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Market Risk and Selection Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a security or other asset may decline due to changes in general market conditions, economic trends or events that are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its investments. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
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&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Operational and Technology Risks&lt;/span&gt;&lt;/span&gt; &#x2014; The Fund is directly and indirectly susceptible to operational and technology risks, including those related to human errors, processing errors, communication errors, systems failures, cybersecurity incidents, and the use of artificial intelligence and machine learning (&#x201c;AI&#x201d;), which may result in losses for the Fund and its shareholders or may impair the Fund&#x2019;s operations. While the Fund&#x2019;s service providers are required to have appropriate operational, information security and cybersecurity risk management policies and procedures, their methods of risk management may differ from those of the Fund. Operational and technology risks for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and may cause the Fund&#x2019;s investments in such issuers to lose value.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
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&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Risk of Investing in the United States&lt;/span&gt;&lt;/span&gt; &#x2014; Certain changes in the U.S. economy, such as when the U.S. economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
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&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Stable Net Asset Value Risk&lt;/span&gt;&lt;/span&gt; &#x2014; The Fund may not be able to maintain a stable net asset value (&#x201c;NAV&#x201d;) of $1.00 per share at all times. If the Fund fails to maintain a stable NAV (or if there is a perceived threat of such a failure), the Fund, along with other money market funds, could be subject to increased redemption activity.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
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&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;Variable and Floating Rate Instrument Risk&lt;/span&gt;&lt;/span&gt; &#x2014; Variable and floating rate securities provide for periodic adjustment in the interest rate paid on the securities. Securities with floating or variable interest rates can be less sensitive to interest rate changes than securities with fixed interest rates, but may decline in value if their coupon rates do not reset as high, or as quickly, as comparable market interest rates, and generally carry lower yields than fixed securities of the same maturity. These securities will not generally increase in value if interest rates decline. A decline in interest rates may result in a reduction in income received from variable and floating rate securities held by the Fund and may adversely affect the value of the Fund&#x2019;s shares. Benchmark interest rates may not accurately track market interest rates. Although floating rate securities are less sensitive to interest rate risk than fixed-rate securities, they are subject to credit risk and default risk, which could impair their value.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
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&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;"&gt; 
&lt;tr style="page-break-inside: avoid;"&gt; 
&lt;td style="width: 2%; vertical-align: top; text-align: left;"&gt;&lt;span style="font-family: times new roman;"&gt;&#x220e;&lt;/span&gt;&lt;/td&gt; 
&lt;td style="width: 1%; vertical-align: top;"&gt;&#160;&lt;/td&gt; 
&lt;td style="vertical-align: top; text-align: left;"&gt; &lt;div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;"&gt;&lt;span style="font-weight: bold;"&gt;&lt;span style="font-style: italic;"&gt;When-Issued and Delayed Delivery Securities and Forward Commitments Risk&lt;/span&gt;&lt;/span&gt; &#x2014; When-issued and delayed delivery securities and forward commitments involve the risk that the security the Fund buys will lose value prior to its delivery. There also is the risk that the security will not be issued or that the other party to the transaction will not meet its obligation. If this occurs, the Fund may lose both the investment opportunity for the assets it set aside to pay for the security and any gain in the security&#x2019;s price.&lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</oef:RiskTextBlock>
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      id="t_106_a0c60a7c_da38_f602_b6c7_ee02394eb039"> &lt;div style="margin-top: 4pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;The information shows you how the Fund&#x2019;s performance has varied year by year and provides some indication of the risks of investing in the Fund. The Fund is a money market fund managed pursuant to the requirements of Rule&#160;2a&#x2011;7 under the Investment Company Act. To the extent that dividends and distributions have been paid by the Fund, the performance information for the Fund in the chart and table assumes reinvestment of the dividends and distributions. As with all such investments, past performance is not an indication of future results. The bar chart and table do not reflect separate account fees and expenses. If they did, returns would be less than those shown. If the Fund&#x2019;s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund&#x2019;s returns would have been lower.&lt;/div&gt; </oef:PerformanceNarrativeTextBlock>
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      id="t_96_98949696_8845_140f_e61e_26e773b7af70">The information shows you how the Fund&#x2019;s performance has varied year by year and provides some indication of the risks of investing in the Fund.</oef:PerformanceInformationIllustratesVariabilityOfReturns>
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    <oef:BarChartHeading
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      id="t_109_77875c95_bff4_bf30_24d6_14b46b71417f">ANNUAL TOTAL RETURNSBlackRock Government Money Market PortfolioAs of 12/31</oef:BarChartHeading>
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      id="t_108_8cd523c9_628c_4077_7f92_2bc6a3742173">For the periods ended 12/31/25Average Annual Total Returns</oef:PerformanceTableHeading>
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      id="t_110_0ed45b34_3052_6075_4f15_eb001e47895d">&lt;div style="margin-top: 6pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"&gt;To obtain the Fund&#x2019;s current 7-day yield, visit the Fund&#x2019;s website at www.blackrock.com/cash.&lt;/div&gt;</oef:PerformanceTableNarrativeTextBlock>
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