v3.25.0.1
Label Element Value
iShares iBonds Oct 2031 Term TIPS ETF  
Risk/Return: rr_RiskReturnAbstract  
Risk/Return [Heading] rr_RiskReturnHeading iSHARES® iBONDS® OCT 2031 TERM TIPS ETF Ticker: IBIHStock Exchange: NYSE Arca
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The iShares iBonds Oct 2031 Term TIPS ETF (the “Fund”) seeks to track the investment results of an index composed of inflation-protected U.S. Treasury bonds maturing in 2031.
Expense [Heading] rr_ExpenseHeading Fees and Expenses
Expense Narrative [Text Block] rr_ExpenseNarrativeTextBlock
The following table describes the fees and expenses that you will incur if you buy, hold and sell shares of the Fund. The investment advisory agreement between iShares Trust (the “Trust”) and BlackRock Fund Advisors (“BFA”) (the “Investment Advisory Agreement”) provides that BFA will pay all operating expenses of the Fund, except: (i) the management fees, (ii) interest expenses, (iii) taxes, (iv) expenses incurred with respect to the acquisition and disposition of portfolio securities and the execution of portfolio transactions, including brokerage commissions, (v) distribution fees or expenses, and (vi) litigation expenses and any extraordinary expenses. The Fund may incur “Acquired Fund Fees and Expenses.” Acquired Fund Fees and Expenses reflect the Fund's pro rata share of the fees and expenses incurred indirectly by the Fund as a result of investing in other investment companies. The impact of Acquired Fund Fees and Expenses is included in the Fund's total return but is not included in the Fund's ratio of expenses to average net assets. Both figures are shown in the Financial Highlights section of the Fund's prospectus (the “Prospectus”). BFA, the investment adviser to the Fund, has contractually agreed to waive a portion of its management fees in an amount equal to the Acquired Fund Fees and Expenses, if any, attributable to investments by the Fund in other funds advised by BFA or its affiliates through the termination date of the Fund, on or about October 15, 2031. The contractual waiver may be terminated prior to the Fund's termination only upon the written agreement of the Trust and BFA.
You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Operating Expenses Caption [Text] rr_OperatingExpensesCaption Annual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investments)1
Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination October 15, 2031
Portfolio Turnover [Heading] rr_PortfolioTurnoverHeading Portfolio Turnover.
Portfolio Turnover [Text Block] rr_PortfolioTurnoverTextBlock The Fund may pay 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 higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in the Annual Fund Operating Expenses or in the Example, affect the Fund’s performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 0% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate none
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees The impact of Acquired Fund Fees and Expenses is included in the Fund's total return but is not included in the Fund's ratio of expenses to average net assets. Both figures are shown in the Financial Highlights section of the Fund's prospectus (the “Prospectus”).
Expense Example [Heading] rr_ExpenseExampleHeading Example.
Expense Example Narrative [Text Block] rr_ExpenseExampleNarrativeTextBlock This Example is intended to help you compare the cost of owning shares of the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then sell all of your shares at the end of those periods.Fund expenses (and any applicable waivers) are calculated only through October 15, 2031 because the Fund is scheduled to cease operations and liquidate by that date. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Strategy [Heading] rr_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock
The Fund seeks to track the investment results of the ICE 2031 Maturity US Inflation-Linked Treasury Index (the “Underlying Index”), which consists of inflation-protected public obligations of the U.S. Treasury, commonly known as “TIPS,” that are scheduled to mature between January 1, 2031 and October 15, 2031, inclusive. The Fund is a term fund that will terminate on or about October 15, 2031, at which time it will distribute its remaining net assets to shareholders pursuant to a plan of liquidation. The Fund does not seek to return any predetermined amount at maturity or in periodic distributions. As of October 31, 2024, there were 2 components in the Underlying Index.
TIPS are securities issued by the U.S. Treasury that are designed to provide inflation protection to investors. TIPS are income-generating instruments whose interest and principal payments are adjusted for inflation—a sustained increase in prices that erodes the purchasing power of money. The inflation adjustment, which is typically applied monthly to the principal of the bond, follows a designated inflation index, the non-seasonally adjusted Consumer Price Index for All Urban Consumers (“CPI”), and TIPS’ principal payments are adjusted according to changes in the CPI. A fixed coupon rate is applied to the inflation-adjusted principal so that, as inflation rises, both the principal value and the interest payments increase. This can provide investors with a hedge against inflation, as it helps preserve the purchasing power of an investment. Because of this inflation adjustment feature, inflation-protected bonds typically have lower yields than conventional fixed-rate bonds.
The securities in the Underlying Index must be denominated in U.S. dollars and have (1) a fixed coupon schedule, (2) a remaining term to final maturity of more than one day as of the monthly rebalancing date and (3) at least $1 billion of outstanding face value (excluding amounts held by the Federal Reserve System Open Market Account (“SOMA”)). Excluded from the Underlying Index are government agency debt with or without a government guarantee, securities issued or marketed primarily to retail investors, floating rate notes, cash management and Treasury bills, original issue zero coupon securities and Separate Trading of Registered Interest and Principal Securities (or “STRIPs”). However, the amounts outstanding of qualifying securities in the Underlying Index are not reduced by any portions of such securities that have been stripped after inclusion in the Underlying Index. Index constituents are market capitalization weighted based on amounts outstanding reduced by amounts held by the Federal Reserve SOMA times price plus accrued interest.
The Underlying Index is rebalanced on the last calendar day of each month. New issues must settle on or before the following calendar month end rebalancing date in order to qualify for
inclusion for such following month (e.g., an issue must settle on or before August 31 in order to be included in the index on July 31). The securities in the Underlying Index are updated on the last calendar day of each month. Cash flows from bond payments that are received during the month are retained in the Underlying Index until the end of the month and then are removed as part of the rebalancing. When cash or a security is removed as part of the rebalancing, it effectively increases the weighting of the remaining securities in the Underlying Index, and the Fund is required to invest in the remaining securities to bring its holdings in line with the Underlying Index. Cash does not earn any reinvestment income while it is held in the Underlying Index.
The Fund will invest at least 80% of its assets in the component securities of the Underlying Index, and the Fund will invest at least 90% of its assets in U.S. Treasury securities that BFA believes will help the Fund track the Underlying Index, in each case except as described below. The Fund will invest no more than 10% of its assets in futures, options and swaps contracts that BFA believes will help the Fund track the Underlying Index. Cash and cash equivalent investments associated with a derivative position will be treated as part of that position for the purposes of calculating the percentage of investments included in the Underlying Index.
The Fund seeks to track the investment results of the Underlying Index before fees and expenses of the Fund. In the last six months of operation, as the bonds held by the Fund mature, the proceeds will typically be reinvested by the Fund in investments already in the Underlying Index but may also be invested in other cash and cash equivalents as determined by BFA. To the extent that the Fund invests in money market or similar funds, it will incur the fees and expenses of such funds.
By October 15, 2031, the Fund is expected to consist almost entirely of cash. On or around this date, the Fund will wind up and terminate. After appropriate provision is made for any Fund liabilities, its net assets will be distributed to then-current shareholders pursuant to a plan of liquidation. The Fund's termination was approved by a majority of the Trust's Board of Trustees (the “Board”) and does not require additional approval by Fund shareholders. The Board may extend the termination date if a majority of the Board determines the extension to be in the best interest of the Fund.
BFA uses an indexing approach to try to achieve the Fund’s investment objective. The Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued.
Indexing may eliminate the chance that the Fund will substantially outperform the Underlying Index but also may reduce some of the risks of active management, such as poor security selection. Indexing seeks to achieve lower costs and better after-tax performance by aiming to keep portfolio turnover low in comparison to actively managed investment companies.
BFA uses a representative sampling indexing strategy to manage the Fund. “Representative sampling” is an indexing strategy that involves investing in a representative sample of securities that collectively has an investment profile similar to that of an applicable underlying index. The securities selected are expected to have, in the aggregate, investment characteristics (based on factors such as market value and industry weightings),
fundamental characteristics (such as return variability, duration (i.e., a security's price sensitivity to a change in interest rates), maturity or credit ratings and yield) and liquidity measures similar to those of an applicable underlying index. The Fund may or may not hold all of the securities in the Underlying Index.
The Fund may lend securities representing up to one-third of the value of the Fund's total assets (including the value of any collateral received).
The Underlying Index is owned, maintained and administered by ICE Data Indices, LLC (the “Index Provider” or “IDI”), which is independent of the Fund and BFA. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index.
Risk [Heading] rr_RiskHeading Summary of Principal Risks
Bar Chart and Performance Table [Heading] rr_BarChartAndPerformanceTableHeading Performance Information
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock
The performance information below illustrates how the Fund’s performance has varied over different periods and provides some indication of the risks of investing in the Fund. The bar chart shows how the performance of the Fund has varied from one calendar year to another over the periods shown. The table compares the Fund’s performance to that of an appropriate broad-based securities market index and the Underlying Index. Fund returns assume the reinvestment of any dividends and distributions. The Fund’s returns reflect the impact of any agreements to waive or reimburse expenses, which would reduce performance if not in effect. Past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated performance information, including the Fund’s current NAV, may be obtained by visiting www.iShares.com or by calling 1-800-iShares (1-800-474-2737) (toll free).
Performance Information Illustrates Variability of Returns [Text] rr_PerformanceInformationIllustratesVariabilityOfReturns The performance information below illustrates how the Fund’s performance has varied over different periods and provides some indication of the risks of investing in the Fund. The bar chart shows how the performance of the Fund has varied from one calendar year to another over the periods shown. The table compares the Fund’s performance to that of an appropriate broad-based securities market indexand the Underlying Index.
Performance Availability Phone [Text] rr_PerformanceAvailabilityPhone 1-800-iShares (1-800-474-2737) (toll free)
Performance Availability Website Address [Text] rr_PerformanceAvailabilityWebSiteAddress www.iShares.com
Performance Past Does Not Indicate Future [Text] rr_PerformancePastDoesNotIndicateFuture Past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future.
Bar Chart [Heading] rr_BarChartHeading Calendar Year-by-Year Returns 
Bar Chart Closing [Text Block] rr_BarChartClosingTextBlock
 
Return (%)
Period Ended
During the period shown in the chart:
Best Quarter
4.52%
September 30, 2024
Worst Quarter
-3.23%
December 31, 2024
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns (for the periods ended December 31, 2024) 
Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown are not relevant to tax-exempt investors or investors who hold shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”).
Performance Table Explanation after Tax Higher rr_PerformanceTableExplanationAfterTaxHigher Fund returns after taxes on distributions and sales of Fund shares are calculated assuming that an investor has sufficient capital gains of the same character from other investments to offset any capital losses from the sales of Fund shares. As a result, Fund returns after taxes on distributions and sales of Fund shares may exceed Fund returns before taxes and/or returns after taxes on distributions.
Performance Table Narrative rr_PerformanceTableNarrativeTextBlock
After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown are not relevant to tax-exempt investors or investors who hold shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). Fund returns after taxes on distributions and sales of Fund shares are calculated assuming that an investor has sufficient capital gains of the same character from other investments to offset any capital losses from the sales of Fund shares. As a result, Fund returns after taxes on distributions and sales of Fund shares may exceed Fund returns before taxes and/or returns after taxes on distributions.
iShares iBonds Oct 2031 Term TIPS ETF | Risk Lose Money [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock As with any investment, you could lose all or part of your investment in the Fund, and the Fund's performance could trail that of other investments.
iShares iBonds Oct 2031 Term TIPS ETF | U S Treasury Obligations Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
U.S. Treasury Obligations Risk. U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics and may provide relatively lower returns than those of other securities. Changes in the U.S. government’s financial condition or credit rating may cause the value of U.S. Treasury obligations to decline. Direct obligations of the U.S. Treasury have historically involved little risk of loss of principal if held to maturity, but the market value of such securities is not guaranteed and may fluctuate. Although 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.
iShares iBonds Oct 2031 Term TIPS ETF | Inflation Indexed Bonds Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Inflation-Indexed Bonds Risk. The principal value of an investment in the Fund is not protected or otherwise guaranteed by virtue of the Fund's investments in inflation-indexed bonds.
iShares iBonds Oct 2031 Term TIPS ETF | Interest Rate Risks [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Interest Rate Risk. Interest rate risk refers to the risk of fluctuations in the value of a fixed-income security due to changes in the general level of interest rates. Interest rate changes can be sudden and unpredictable and are influenced by a number of factors, including government policy, monetary policy, inflation expectations, perceptions of risk, and supply and demand for fixed-income securities. An increase in interest rates generally will cause the value of fixed-income securities to decline. Securities with longer maturities generally are more sensitive to interest rate changes and subject to greater fluctuations in value. Changes in interest rates may have unpredictable effects on fixed-income markets and result in heightened volatility and lower liquidity for certain instruments, which may adversely affect a Fund’s performance. During periods of very low or negative interest rates, a Fund may be unable to maintain positive returns or pay dividends to shareholders.
iShares iBonds Oct 2031 Term TIPS ETF | Market Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Market Risk. The Fund could lose money over short periods due to short-term market movements and over longer periods during more prolonged market downturns. Local, regional or global events such as war, acts of terrorism, pandemics or other public health issues, recessions, the prospect or occurrence of a sovereign default or other financial crisis, or other events could have a significant impact on the Fund and its investments and could result in increased premiums or discounts to the Fund’s NAV.
iShares iBonds Oct 2031 Term TIPS ETF | Index Related Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Index-Related Risk. The Index Provider may rely on various sources of information to assess the criteria of components of the Underlying Index, including information that may be based on assumptions and estimates. Neither the Fund nor BFA can offer assurances that the Index Provider’s methodology or sources of information will provide an accurate assessment of included components or will result in the Fund meeting its investment objective. Errors in index data, index computations or the construction of the Underlying Index in accordance with its methodology may occur, and the Index Provider may not identify or correct them promptly or at all, which may have an adverse impact on the Fund and its shareholders. Unusual market conditions or other unforeseen circumstances (such as natural disasters, political unrest or war) may impact the Index Provider or a third-party data provider and could cause the Index Provider to postpone a scheduled rebalance. This could cause the Underlying Index to vary from its normal or expected composition.
iShares iBonds Oct 2031 Term TIPS ETF | Asset Class Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Asset Class Risk. The securities and other assets in the Underlying Index or in the Fund’s portfolio may underperform in comparison to financial markets generally, a particular financial market, another index, or other asset classes.
iShares iBonds Oct 2031 Term TIPS ETF | Assets Under Management AUM Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Assets Under Management (AUM) Risk. From time to time, an Authorized Participant (as defined below in Authorized Participant Concentration Risk), a third-party investor, the Fund’s adviser, an affiliate of the Fund’s adviser, or another fund may invest in the Fund and hold its investment for a specific period of time to allow the Fund to achieve size or scale. There can be no assurance that any such entity would not redeem its investment or that the size of the Fund would be maintained at such levels, which could negatively impact the Fund.
iShares iBonds Oct 2031 Term TIPS ETF | Authorized Participant Concentration Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Authorized Participant Concentration Risk.  An “Authorized Participant” is a member or participant of a clearing agency registered with the SEC, which has a written agreement with the Fund or one of its service providers that allows the Authorized Participant to place orders for the purchase and redemption of creation units (“Creation Units”). Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund. There are a limited number of institutions that may act as Authorized Participants for the Fund, including on an agency basis on behalf of other market participants. No Authorized Participant is obligated to engage in creation or redemption transactions. To the extent that Authorized Participants exit the business or do not place creation or redemption orders for the Fund and no other Authorized Participant places orders, Fund shares are more likely to trade at a premium or discount to NAV and possibly face trading halts or delisting.
iShares iBonds Oct 2031 Term TIPS ETF | Concentration Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Concentration Risk. The Fund may be susceptible to an increased risk of loss, including losses due to adverse events that affect the Fund’s investments more than the market as a whole,
to the extent that the Fund’s investments are concentrated in the securities or other assets of one or more issuers, countries or other geographic units, markets, industries, project types, or asset classes.
iShares iBonds Oct 2031 Term TIPS ETF | Cybersecurity Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Cybersecurity Risk. Failures or breaches of the electronic systems of the Fund, its adviser, distributor, Index Provider, other service providers, counterparties, or issuers of assets in which the Fund invests may cause disruptions that negatively impact the Fund and its shareholders. While the Fund has established business continuity plans and risk management systems seeking to address system breaches or failures, there are inherent limitations in such plans and systems. The Fund cannot control the cybersecurity plans and systems of its service providers, counterparties, and other third parties whose activities affect the Fund. In addition, cyber incidents may adversely impact the issuers of securities in which the Fund invests, which may cause such investments to lose value.
iShares iBonds Oct 2031 Term TIPS ETF | Declining Yield Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Declining Yield Risk. During the six months prior to the Fund’s planned termination date, the Fund’s yield may move toward prevailing money market rates and may be lower than the yields of the bonds previously held by the Fund and lower than prevailing yields for bonds in the market.
iShares iBonds Oct 2031 Term TIPS ETF | Income Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Income Risk. The Fund's income may decline if interest rates fall. This decline in income can occur because the Fund may subsequently invest in lower-yielding bonds as bonds in its portfolio mature or are near maturity, or bonds in the Underlying Index are substituted, or the Fund otherwise needs to purchase additional bonds. As the Fund does not seek to return any predetermined amount at maturity or in periodic distributions, the amount of income generated by the Fund may vary during its term.
iShares iBonds Oct 2031 Term TIPS ETF | Issuer Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Issuer Risk. The performance of the Fund depends on the performance of individual securities or other assets to which the Fund has exposure. The value of securities or other assets may decline, or perform differently from the market as a whole, due to changes in the financial condition or credit rating of the issuer or counterparty.
iShares iBonds Oct 2031 Term TIPS ETF | Management Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Management Risk. The Fund generally does not attempt to take defensive positions under any market conditions, including declining markets. As the Fund will not fully replicate the Underlying Index and may hold securities or other assets not included in the Underlying Index, it is subject to the risk that the investment strategy of BFA may not produce the intended results. There is no guarantee that the Fund’s investment results will have a high degree of correlation to those of the Underlying Index or that the Fund will achieve its investment objective.
iShares iBonds Oct 2031 Term TIPS ETF | Market Trading Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Market Trading Risk. The Fund faces numerous market trading risks, including the potential lack of an active market for Fund shares (including through a trading halt), losses from trading in secondary markets, periods of high volatility, and disruptions in the process of creating and redeeming Fund shares. Any of these factors, among others, may lead to the Fund’s shares trading in the secondary market at a premium or discount to NAV or to the intraday value of the Fund’s portfolio holdings. If you buy Fund shares at a time when the market price is at a premium to NAV or
sell Fund shares at a time when the market price is at a discount to NAV, you may pay significantly more or receive significantly less than the underlying value of the Fund shares.
iShares iBonds Oct 2031 Term TIPS ETF | Operational Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Operational Risk. The Fund is exposed to operational risks arising from a number of factors, including, but not limited to, human error, processing and communication errors, errors of the Fund’s service providers, counterparties or other third parties, failed or inadequate processes and technology or systems failures. The Fund and BFA seek to reduce these operational risks through controls and procedures. However, these measures do not address every possible risk and may be inadequate to address significant operational risks.
iShares iBonds Oct 2031 Term TIPS ETF | Risk of Investing in the U S [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Risk of Investing in the U.S. Investing in U.S. issuers subjects the Fund to legal, regulatory, political, currency, security, and economic risks that are specific to the U.S. Certain changes in the U.S., such as a weakening of the U.S. economy or a decline in its financial markets, may have an adverse effect on U.S. issuers.
iShares iBonds Oct 2031 Term TIPS ETF | Securities Lending Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Securities Lending Risk. The Fund may engage in securities lending. Securities lending involves the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. These events could also trigger adverse tax consequences for the Fund.
iShares iBonds Oct 2031 Term TIPS ETF | Small Fund Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Small Fund Risk. When the Fund’s size is small, the Fund may experience low trading volume and wide bid/ask spreads. In addition, the Fund may face the risk of being delisted if it does not meet certain requirements set by the listing exchange. Any resulting liquidation of the Fund could lead to elevated transaction costs for the Fund and negative tax consequences for its shareholders.
iShares iBonds Oct 2031 Term TIPS ETF | Tracking Error Risk [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock
Tracking Error Risk. The Fund may be subject to “tracking error,” which is the divergence of the Fund’s performance from that of the Underlying Index. Tracking error may occur due to a number of factors, including differences between the securities and other assets held in the Fund’s portfolio and those included in the Underlying Index; differences in the timing and methodologies used to value securities and other assets; transaction costs and other expenses incurred by the Fund that the Underlying Index does not incur; the Fund’s holding of uninvested cash; differences in the timing of the accrual or the valuation of dividends or interest received by the Fund or distributions paid to Fund shareholders; tax gains or losses; the requirements for the Fund to maintain pass-through tax treatment; portfolio transactions carried out to minimize the distribution of capital gains to shareholders; the acceptance of custom baskets; changes to the Underlying Index; and impacts to the Fund of complying with certain regulatory requirements or limits. Tracking error risk may be heightened during times of increased market volatility or other unusual market conditions. Until the Fund reaches greater scale, it may experience higher tracking error than is typical for similar index ETFs.
iShares iBonds Oct 2031 Term TIPS ETF | iShares iBonds Oct 2031 Term TIPS ETF  
Risk/Return: rr_RiskReturnAbstract  
Management Fees rr_ManagementFeesOverAssets 0.10% [1]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none [1]
Other Expenses rr_OtherExpensesOverAssets none [1]
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets none [1],[2]
Total Annual Fund Operating Expenses rr_ExpensesOverAssets 0.10% [1]
Fee Waiver and/or Expense Reimbursement rr_FeeWaiverOrReimbursementOverAssets none [1],[2]
Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement rr_NetExpensesOverAssets 0.10% [1]
1 Year rr_ExpenseExampleYear01 $ 10
3 Years rr_ExpenseExampleYear03 32
5 Years rr_ExpenseExampleYear05 56
Maturity ist_ExpenseExampleMaturity $ 78
2024 rr_AnnualReturn2024 1.86%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Best Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Sep. 30, 2024
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 4.52%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Worst Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2024
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (3.23%)
One Year rr_AverageAnnualReturnYear01 1.86%
Since Fund Inception rr_AverageAnnualReturnSinceInception 4.24%
Inception Date rr_AverageAnnualReturnInceptionDate Sep. 19, 2023
iShares iBonds Oct 2031 Term TIPS ETF | Return After Taxes on Distributions | iShares iBonds Oct 2031 Term TIPS ETF  
Risk/Return: rr_RiskReturnAbstract  
One Year rr_AverageAnnualReturnYear01 0.11%
Since Fund Inception rr_AverageAnnualReturnSinceInception 2.61%
iShares iBonds Oct 2031 Term TIPS ETF | Return After Taxes on Distributions and Sale of Fund Shares | iShares iBonds Oct 2031 Term TIPS ETF  
Risk/Return: rr_RiskReturnAbstract  
One Year rr_AverageAnnualReturnYear01 1.10%
Since Fund Inception rr_AverageAnnualReturnSinceInception 2.55%
iShares iBonds Oct 2031 Term TIPS ETF | ICE BofA US Broad Market Index (Returns do not reflect deductions for fees, expenses or taxes)  
Risk/Return: rr_RiskReturnAbstract  
One Year rr_AverageAnnualReturnYear01 1.47% [3]
Since Fund Inception rr_AverageAnnualReturnSinceInception 5.25% [3]
iShares iBonds Oct 2031 Term TIPS ETF | ICE 2031 Maturity US Inflation-Linked Treasury Index (Returns do not reflect deductions for fees, expenses or taxes)  
Risk/Return: rr_RiskReturnAbstract  
One Year rr_AverageAnnualReturnYear01 1.95%
Since Fund Inception rr_AverageAnnualReturnSinceInception 4.33%
[1] Operating expenses paid by BFA under the Investment Advisory Agreement exclude Acquired Fund Fees and Expenses, if any.
[2] The amount rounded to 0.00%.
[3] The Fund has added this broad-based index in response to new regulatory requirements.