| Label | Element | Value |
|---|---|---|
| Risk Return Abstract | rr_RiskReturnAbstract | |
| Registrant Name | dei_EntityRegistrantName | VANGUARD SPECIALIZED FUNDS |
| Prospectus Date | rr_ProspectusDate | May 25, 2023 |
| Retail | Vanguard Energy Fund | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| Risk/Return [Heading] | rr_RiskReturnHeading | <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Fund Summary</span> |
| Objective [Heading] | rr_ObjectiveHeading | <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> |
| Objective, Primary [Text Block] | rr_ObjectivePrimaryTextBlock | The Fund seeks to provide long-term capital appreciation. |
| Expense [Heading] | rr_ExpenseHeading | <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> |
| Expense Narrative [Text Block] | rr_ExpenseNarrativeTextBlock | The following table describes the fees and expenses you may pay if you buy, hold, and sell Investor Shares or Admiral Shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and example below. |
| Shareholder Fees Caption [Text] | rr_ShareholderFeesCaption | <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;margin-left:0%;">(Fees paid directly from your investment)</span> |
| Operating Expenses Caption [Text] | rr_OperatingExpensesCaption | <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;margin-left:0%;">(Expenses that you pay each year as a percentage of the value of your investment)</span> |
| Portfolio Turnover [Heading] | rr_PortfolioTurnoverHeading | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> |
| Portfolio Turnover [Text Block] | rr_PortfolioTurnoverTextBlock | The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense examples, reduce the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 16% of the average value of its portfolio. |
| Portfolio Turnover, Rate | rr_PortfolioTurnoverRate | 16.00% |
| Expense Example [Heading] | rr_ExpenseExampleHeading | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Examples</span> |
| Expense Example Narrative [Text Block] | rr_ExpenseExampleNarrativeTextBlock | The following examples are intended to help you compare the cost of investing in the Fund’s Investor Shares or Admiral Shares with the cost of investing in other mutual funds. They illustrate the hypothetical expenses that you would incur over various periods if you were to invest $10,000 in the Fund's shares. These examples assume that the shares provide a return of 5% each year and that total annual fund operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you were to redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: |
| Strategy [Heading] | rr_StrategyHeading | <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> |
| Strategy Narrative [Text Block] | rr_StrategyNarrativeTextBlock | Under normal circumstances, the Fund invests at least 80% of its assets in the common stocks of companies principally engaged in activities in the energy industry, such as the exploration, production, and transmission of energy or energy fuels; the making and servicing of component products for such activities; energy research; and energy conservation or pollution control. The Fund may invest in foreign stocks as part of its principal investment strategy. |
| Risk [Heading] | rr_RiskHeading | <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Risks</span> |
| Risk Narrative [Text Block] | rr_RiskNarrativeTextBlock | An investment in the Fund could lose money over short or long periods of time.You should expect the Fund's share price and total return to fluctuate within a wide range. The Fund is subject to the following risks, which could affect the Fund's performance:• Industry concentration risk, which is the chance that there will be particular problems affecting an entire industry. Any fund that concentrates in a particular industry will generally be more volatile than a fund that invests more broadly. Because the Fund normally invests at least 80% of its assets in the common stocks of companies principally engaged in activities in the energy industry, the Fund’s performance largely depends—for better or for worse—on the overall condition of the energy industry. The energy industry could be adversely affected by energy prices, supply-and-demand for energy resources, and various political, regulatory, and economic factors. Additionally, commodity prices may have a significant impact on the stock prices of energy companies.• Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Fund’s investments in foreign stocks can be riskier than U.S. stock investments. Foreign stocks may be more volatile and less liquid than U.S. stocks. The prices of foreign stocks and the prices of U.S. stocks may move in opposite directions.• Manager risk, which is the chance that poor security selection will cause the Fund to underperform relevant benchmarks or other funds with a similar investment objective. In addition, significant investments in the utilities sector and the integrated oil and gas sector subjects the Fund to proportionately higher exposure to the risks of these sectors.• Country risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value of securities issued by companies in foreign countries. Because the Fund may invest a large portion of its securities of companies located in any one country or region, the Fund's performance may be hurt disproportionately by the poor performance of its investments in that area.• Currency risk, which is the chance that the value of a foreign investment, measured in U.S. dollars, will decrease because of unfavorable changes in currency exchange rates.• Asset concentration risk, which is the chance that, because the Fund tends to invest a high percentage of assets in its ten largest holdings, the Fund’s performance may be hurt disproportionately by the poor performance of relatively few stocks.• Nondiversification risk, which is the chance that the Fund’s performance may be hurt disproportionately by the poor performance of relatively few stocks or even a single stock. The Fund is considered nondiversified, which means that it may invest a greater percentage of its assets in the securities of particular issuers as compared with diversified mutual funds.An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. |
| Risk Lose Money [Text] | rr_RiskLoseMoney | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">An investment in the Fund could lose money over short or long periods of time.</span> |
| Risk Not Insured Depository Institution [Text] | rr_RiskNotInsuredDepositoryInstitution | <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> |
| Risk Nondiversified Status [Text] | rr_RiskNondiversifiedStatus | <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Nondiversification risk</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">, which is the chance that the Fund’s performance may be hurt disproportionately by the poor performance of relatively few stocks or even a single stock. The Fund is considered nondiversified, which means that it may invest a greater percentage of its assets in the securities of particular issuers as compared with diversified mutual funds.</span> |
| Bar Chart and Performance Table [Heading] | rr_BarChartAndPerformanceTableHeading | <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> |
| Performance Narrative [Text Block] | rr_PerformanceNarrativeTextBlock | The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund‘s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the share classes presented compare with those of relevant market indexes, which have investment characteristics similar to those of the Fund. The Spliced Energy Index reflects the performance of the MSCI ACWI Energy Index through October 20, 2020, and the MSCI Energy + Utilities Index thereafter. Returns for the MSCI indexes shown are adjusted for withholding taxes. Keep in mind that the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447. |
| Performance Information Illustrates Variability of Returns [Text] | rr_PerformanceInformationIllustratesVariabilityOfReturns | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund‘s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the share classes presented compare with those of relevant market indexes, which have investment characteristics similar to those of the Fund</span> |
| Performance Availability Phone [Text] | rr_PerformanceAvailabilityPhone | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">800-662-7447</span> |
| Performance Availability Website Address [Text] | rr_PerformanceAvailabilityWebSiteAddress | <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> |
| Bar Chart [Heading] | rr_BarChartHeading | <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Energy Fund Investor Shares</span><span style="font-family:Arial;font-size:5pt;font-weight:bold;position:relative;top:-3.25pt;">1</span> |
| Bar Chart Closing [Text Block] | rr_BarChartClosingTextBlock | During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were: |
| Performance Table Heading | rr_PerformanceTableHeading | <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2022</span> |
| Performance Table Uses Highest Federal Rate | rr_PerformanceTableUsesHighestFederalRate | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> |
| Performance Table Not Relevant to Tax Deferred | rr_PerformanceTableNotRelevantToTaxDeferred | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> |
| Performance Table One Class of after Tax Shown [Text] | rr_PerformanceTableOneClassOfAfterTaxShown | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are shown only for the Investor </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Shares and may differ for each share class. After-tax returns are </span> |
| Performance Table Explanation after Tax Higher | rr_PerformanceTableExplanationAfterTaxHigher | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> |
| Performance Table Closing [Text Block] | rr_PerformanceTableClosingTextBlock | Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. Please note that after-tax returns are shown only for the Investor Shares and may differ for each share class. After-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder. |
| Retail | Vanguard Energy Fund | Investor Shares | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| Purchase Fee | rr_MaximumCumulativeSalesChargeOverOther | none |
| Sales Charge (Load) Imposed on Purchases | rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice | none |
| Sales Charge (Load) Imposed on Reinvested Dividends | rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther | none |
| Redemption Fee | rr_RedemptionFeeOverRedemption | none |
| Account Service Fee Per Year (for certain fund account balances below $1,000,000) | rr_MaximumAccountFee | $ 20 |
| Management Fees | rr_ManagementFeesOverAssets | 0.44% |
| 12b-1 Distribution Fee | rr_DistributionAndService12b1FeesOverAssets | none |
| Other Expenses | rr_OtherExpensesOverAssets | 0.02% |
| Total Annual Fund Operating Expenses | rr_ExpensesOverAssets | 0.46% |
| 1 Year | rr_ExpenseExampleYear01 | $ 47 |
| 3 Years | rr_ExpenseExampleYear03 | 148 |
| 5 Years | rr_ExpenseExampleYear05 | 258 |
| 10 Years | rr_ExpenseExampleYear10 | $ 579 |
| 2013 | rr_AnnualReturn2013 | 18.14% |
| 2014 | rr_AnnualReturn2014 | (14.26%) |
| 2015 | rr_AnnualReturn2015 | (21.50%) |
| 2016 | rr_AnnualReturn2016 | 33.10% |
| 2017 | rr_AnnualReturn2017 | 3.17% |
| 2018 | rr_AnnualReturn2018 | (17.15%) |
| 2019 | rr_AnnualReturn2019 | 13.20% |
| 2020 | rr_AnnualReturn2020 | (30.84%) |
| 2021 | rr_AnnualReturn2021 | 27.71% |
| Annual Return 2022 | rr_AnnualReturn2022 | 23.69% |
| Year to Date Return, Label | rr_YearToDateReturnLabel | year-to-date return |
| Bar Chart, Year to Date Return, Date | rr_BarChartYearToDateReturnDate | Mar. 31, 2023 |
| Bar Chart, Year to Date Return | rr_BarChartYearToDateReturn | (1.16%) |
| Highest Quarterly Return, Label | rr_HighestQuarterlyReturnLabel | <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> |
| Highest Quarterly Return, Date | rr_BarChartHighestQuarterlyReturnDate | Jun. 30, 2020 |
| Highest Quarterly Return | rr_BarChartHighestQuarterlyReturn | 16.09% |
| Lowest Quarterly Return, Label | rr_LowestQuarterlyReturnLabel | <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> |
| Lowest Quarterly Return, Date | rr_BarChartLowestQuarterlyReturnDate | Mar. 31, 2020 |
| Lowest Quarterly Return | rr_BarChartLowestQuarterlyReturn | (41.05%) |
| 1 Year | rr_AverageAnnualReturnYear01 | 23.69% |
| 5 Years | rr_AverageAnnualReturnYear05 | 0.48% |
| 10 Years | rr_AverageAnnualReturnYear10 | 1.13% |
| Retail | Vanguard Energy Fund | Admiral Shares | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| Purchase Fee | rr_MaximumCumulativeSalesChargeOverOther | none |
| Sales Charge (Load) Imposed on Purchases | rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice | none |
| Sales Charge (Load) Imposed on Reinvested Dividends | rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther | none |
| Redemption Fee | rr_RedemptionFeeOverRedemption | none |
| Account Service Fee Per Year (for certain fund account balances below $1,000,000) | rr_MaximumAccountFee | $ 20 |
| Management Fees | rr_ManagementFeesOverAssets | 0.36% |
| 12b-1 Distribution Fee | rr_DistributionAndService12b1FeesOverAssets | none |
| Other Expenses | rr_OtherExpensesOverAssets | 0.02% |
| Total Annual Fund Operating Expenses | rr_ExpensesOverAssets | 0.38% |
| 1 Year | rr_ExpenseExampleYear01 | $ 39 |
| 3 Years | rr_ExpenseExampleYear03 | 122 |
| 5 Years | rr_ExpenseExampleYear05 | 213 |
| 10 Years | rr_ExpenseExampleYear10 | $ 480 |
| 1 Year | rr_AverageAnnualReturnYear01 | 23.80% |
| 5 Years | rr_AverageAnnualReturnYear05 | 0.57% |
| 10 Years | rr_AverageAnnualReturnYear10 | 1.20% |
| Retail | Vanguard Energy Fund | Return After Taxes on Distributions | Investor Shares | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| 1 Year | rr_AverageAnnualReturnYear01 | 22.32% |
| 5 Years | rr_AverageAnnualReturnYear05 | (0.40%) |
| 10 Years | rr_AverageAnnualReturnYear10 | 0.20% |
| Retail | Vanguard Energy Fund | Return After Taxes on Distributions and Sale of Fund Shares | Investor Shares | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| 1 Year | rr_AverageAnnualReturnYear01 | 14.89% |
| 5 Years | rr_AverageAnnualReturnYear05 | 0.25% |
| 10 Years | rr_AverageAnnualReturnYear10 | 0.73% |
| Retail | Vanguard Energy Fund | Dow Jones U.S. Total Stock Market Float Adjusted Index (reflects no deduction for fees, expenses, or taxes) | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| 1 Year | rr_AverageAnnualReturnYear01 | (19.53%) |
| 5 Years | rr_AverageAnnualReturnYear05 | 8.65% |
| 10 Years | rr_AverageAnnualReturnYear10 | 12.03% |
| Retail | Vanguard Energy Fund | Spliced Energy Index (reflects no deduction for fees or expenses) | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| 1 Year | rr_AverageAnnualReturnYear01 | 16.40% |
| 5 Years | rr_AverageAnnualReturnYear05 | (1.80%) |
| 10 Years | rr_AverageAnnualReturnYear10 | (0.49%) |
| Retail | Vanguard Energy Fund | MSCI ACWI Energy + Utilities Index (reflects no deduction for fees or expenses) | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| 1 Year | rr_AverageAnnualReturnYear01 | 16.40% |
| 5 Years | rr_AverageAnnualReturnYear05 | |
| 10 Years | rr_AverageAnnualReturnYear10 |