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iShares High Yield Corporate Bond BuyWrite Strategy ETF  
Risk/Return: rr_RiskReturnAbstract  
Risk/Return [Heading] rr_RiskReturnHeading iSHARES® HIGH YIELD CORPORATE BOND BUYWRITE STRATEGY ETF Ticker: HYGW Stock Exchange: Cboe BZX
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The iShares High Yield Corporate Bond BuyWrite Strategy ETF (the “Fund”) seeks to track the investment results of an index that reflects a strategy of holding the iShares iBoxx $ High Yield Corporate Bond ETF while writing (selling) one-month call options to generate income.
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 total returns of the Fund. Acquired Fund Fees and Expenses are not included in the calculation of the ratio of expenses to average net assets 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 so that the Fund’s total annual fund operating expenses after the fee waiver is equal to the Acquired Fund Fees and Expenses attributable to the Fund’s investment in the iShares iBoxx $ High Yield Corporate Bond ETF (“HYG” or the “Underlying Fund”), after taking into account any fee waivers by HYG, plus 0.20% through February 29, 2028. The contractual waiver may be terminated prior to February 29, 2028 only upon 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 apercentage of the value of your investments)
Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination February 29, 2028
Portfolio Turnover [Heading] rr_PortfolioTurnoverHeading Portfolio Turnover.
Portfolio Turnover [Text Block] rr_PortfolioTurnoverTextBlock The Fund or the Underlying Fund may pay transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate for the Fund or the Underlying Fund may indicate higher transaction costs and may cause the Fund or the Underlying Fund to incur increased expenses. These costs, which are not reflected in the Annual Fund Operating Expenses or in the Example (except costs to the Underlying Fund included as part of Acquired Fund Fees and Expenses), affect the Fund’s performance.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees Acquired Fund Fees and Expenses are not included in the calculation of the ratio of expenses to average net assets 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. 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 Cboe HYG BuyWrite Index (the “Underlying Index”), which is provided by Cboe Global Indices, LLC (the “Index Provider” or “Cboe”) and is designed to measure the performance of a strategy of holding the Underlying Fund while writing (selling) one-month call options on the Underlying Fund to generate income. A strategy of holding a stock or basket of stocks and selling call options that reference the stock or basket of stocks is commonly known as a “covered call” or “buy-write” strategy.
The Underlying Index utilizes “European- 
style” call options. Each call option in the Underlying Index has a strike price closest to 100% of the closing value of the Underlying Fund one day prior to the “roll date. The roll date is the day that the Underlying Index closes out open call option positions by purchasing the offsetting call option positions and subsequently writes new call options that will expire the following month. The roll date is the business day preceding the expiration date of the options in the Underlying Index. The Fund will write options that trade on national securities exchanges. Unlike American-style options, European-style options can only be exercised on the expiration date. 
The Fund will seek to write call options up to (but not exceeding) the full amount of shares of the Underlying Fund held in the Fund (i.e., the short position in the call option is offset, or “covered,” by the long position the Fund holds in shares of the Underlying Fund). By writing a call option, the Fund receives a premium and gives the purchaser of the option the right to purchase shares of the Underlying Fund at the strike price of the option at expiration. However, the Fund does not expect to physically settle outstanding option positions as it will generally purchase offsetting call options on the 
roll date as necessary to close out the open call position(s). By writing the call option(s), the Fund will not participate in market gains of the Underlying Fund above the strike price but will fully participate in any market losses if the Underlying Fund declines in value. 
As of August 8, 2022, a significant portion of the Underlying Index is indirectly represented through its holdings in the Underlying Fund by securities of companies in the consumer services industry or sector. 
BFA uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, 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 and the Underlying 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, maturity, credit ratings and yield) and liquidity measures similar to those of an applicable underlying index. The Fund and the Underlying Fund may or may not hold all of the securities in the applicable Underlying Index. In addition, the Fund may write options on different dates than the Underlying Index’s roll date and may write different options than those included in the Underlying Index but that have investment characteristics, fundamental characteristics and liquidity measures, in the aggregate, similar to those in the Underlying Index. 
The Underlying Index is sponsored by Cboe and 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. 
Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. For purposes of this limitation, securities of the U.S. government (including its agencies and instrumentalities) and repurchase agreements collateralized by U.S. government securities are not considered to be issued by members of any industry. 
Strategy Portfolio Concentration [Text] rr_StrategyPortfolioConcentration Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. For purposes of this limitation, securities of the U.S. government (including its agencies and instrumentalities) and repurchase agreements collateralized by U.S. government securities are not considered to be issued by members of any industry. 
Risk [Heading] rr_RiskHeading Summary of Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
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. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund's net asset value per share (“NAV”), 
trading price, yield, total return and ability to meet its investment objective. The order of the below risk factors does not indicate the significance of any particular risk factor. 
Asset Class Risk. Securities and other assets in the Fund's or the Underlying Fund's portfolio may underperform in comparison to the general financial markets, a particular financial market or other asset classes. 
Assets Under Management (AUM) Risk. From time to time, an Authorized Participant (as defined in the Creations and Redemptions section of this Prospectus), a third-party investor, the Fund’s adviser or an affiliate of the Fund’s adviser, or a 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. 
Authorized Participant Concentration Risk. Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund, and none of those Authorized Participants is obligated to engage in creation and/or redemption transactions. The Fund has a limited number of institutions that may act as Authorized Participants on an agency basis (i.e., on behalf of other market participants). To the extent that Authorized Participants exit the business or are unable to proceed with creation or redemption orders with respect to the Fund and no other Authorized Participant is able to step forward to create or redeem, Fund shares may be more likely to trade at a 
premium or discount to NAV and possibly face trading halts or delisting. 
Calculation Methodology Risk. The Underlying Index relies on various sources of information to assess the criteria of issuers included in the Underlying Index, including information that may be based on assumptions and estimates. Neither the Fund nor BFA can offer assurances that the Underlying Index’s calculation methodology or sources of information will provide an accurate assessment of included issuers. 
Call Risk. During periods of falling interest rates, an issuer of a callable bond held by the Underlying Fund may “call” or repay the security before its stated maturity, and the Underlying Fund may have to reinvest the proceeds in securities with lower yields, which would result in a decline in the Fund's or Underlying Fund's income, or in securities with greater risks or with other less favorable features. 
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 or the Underlying Fund's investments are concentrated in the securities and/or other assets of a particular issuer or issuers, country, group of countries, region, market, industry, group of industries, sector, market segment or asset class. 
Consumer Services Industry Risk. Companies in the consumer services industry may be affected by, among other things, changes in the domestic and international economies, exchange rates, competition, consumers' disposable income and consumer preferences. Companies in the 
consumer services industry are facing increased government and regulatory scrutiny and may be subject to adverse government or regulatory action. 
Covered Call Option Risk. By writing covered call options in return for the receipt of premiums, the Fund will give up the opportunity to benefit from potential increases in the value of the Underlying Fund above the exercise prices of the written options, but will continue to bear the risk of declines in the value of the Underlying Fund. The premiums received from the options may not be sufficient to offset any losses sustained from the volatility of the Underlying Fund over time. In addition, the Fund’s ability to sell shares of the Underlying Fund will be limited while the option is in effect unless the Fund extinguishes the option position through the purchase of an offsetting identical option prior to the expiration of the written option. 
The covered call strategy may be subject to imperfect matching or price correlation between the written options and the Underlying Fund, which could reduce the Fund’s returns. Exchanges may suspend the trading of options (for example due to volatile markets or if trading in the Underlying Fund is halted). If trading is suspended, the Fund may be unable to write or purchase options at times that may be desirable or advantageous to the Fund to do so. If the Fund is unable to extinguish the option position before exercise, the Fund may be required to deliver the corresponding shares of the Underlying Fund, resulting in increased transaction costs, tracking error, underinvestment, and potentially the realization of capital gains. Further, this could lead to re-purchasing shares of the Underlying Fund or selling the 
corresponding options at a less favorable price than the fund might have received had the options been extinguished. The Fund uses options which are struck once per month, and the timing of changes in the price of the Underlying Fund may affect the Fund’s performance. For example, if the Underlying Fund experiences a drop in price followed by a quick rebound, the Fund may be unable to fully participate in the rebound if the rebound occurs immediately after the Fund’s roll date. In addition, if trading is suspended, the Fund may be unable to purchase an offsetting option for purposes of closing out an existing written option at the originally scheduled time and date. 
The Fund will be affected by movements in interest rates and bond yields and the resulting share price of the Underlying Fund. In a falling interest rate environment and other environments in which credit spreads narrow, the Underlying Fund is generally expected to appreciate in price, and the Fund may underperform the Underlying Fund as price appreciation for the Fund is limited to the exercise prices of the options written by the Fund. 
Credit Risk. Debt issuers and other counterparties may be unable or unwilling to make timely interest and/or principal payments when due or otherwise honor their obligations. Changes in an issuer’s credit rating or the market’s perception of an issuer’s creditworthiness may also adversely affect the value of the Fund’s or Underlying Fund's investment in that issuer. The degree of credit risk depends on an issuer's or counterparty's financial condition and on the terms of an obligation. 
Cybersecurity Risk. Failures or breaches of the electronic systems of the Fund or the Underlying Fund, the Fund's or the Underlying Fund's adviser, distributor, or other service providers, market makers, Authorized Participants or the issuers of securities in which the Fund or the Underlying Fund invests have the ability to cause disruptions, negatively impact the Fund’s business operations and/or potentially result in financial losses to 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. Furthermore, the Fund cannot control the cybersecurity plans and systems of the Fund’s Index Provider and other service providers, market makers, Authorized Participants or issuers of securities in which the Fund or the Underlying Fund invests. 
Derivatives Risk. The Fund will use covered calls, which are options, in seeking to achieve the Fund’s investment objective. The Fund’s use of options, like investment in other derivatives, may reduce the Fund’s returns or increase volatility. A risk of the Fund’s use of derivatives is that the fluctuations in their values may not correlate with the value of the underlying asset, the performance of the asset class to which the Fund seeks exposure or to the performance of the overall securities markets. Since the Fund’s covered call options are written on shares of the Underlying Fund, if the increase in the price of the Underlying Fund is significantly above the exercise price of a written option, the Fund would likely substantially underperform the Underlying Fund. In addition, implied volatility is one of the primary inputs in 
options pricing. As volatility increases, the value of an option also increases (and vice-versa). Changes in the level of volatility can affect the amount of premium the Fund will receive from writing options and increased volatility may increase the cost the Fund pays to close out an open option position. 
In addition, the Fund's use of derivatives may expose the Fund to risks related to potential operational issues, such as documentation and settlement issues, systems failures, inadequate controls and human error. Derivatives also may involve legal risks, including insufficient documentation, insufficient capacity or authority of a counterparty, and legality and enforceability of a contract. 
Distribution Tax Risk. The Fund currently expects to make distributions on a regular basis. While the Fund will normally pay its income as distributions the Fund's distributions may exceed the Fund's income and gains for the Fund's taxable year. The Fund may be required to reduce its distributions if it has insufficient income. Distributions in excess of the Fund's current and accumulated earnings and profits will be treated as a return of capital. Distributions in excess of the Fund's minimum distribution requirements, but not in excess of the Fund's earnings and profits, will be taxable to Fund shareholders and will not constitute nontaxable returns of capital. A return of capital distribution generally will not be taxable but will reduce the shareholder's cost basis and will result in a higher capital gain or lower capital loss when those Fund shares on which the distribution was received are sold. Once a Fund shareholder's cost basis is 
reduced to zero, further distributions will be treated as capital gain, if the Fund shareholder holds shares of the Fund as capital assets. Because the Fund's distributions may consist of return of capital, the Fund may not be an appropriate investment for investors who do not want their principal investment in the Fund to decrease over time or who do not wish to receive return of capital in a given period. 
Geographic Risk. A natural disaster could occur in a geographic region in which the Fund or Underlying Fund invests, which could adversely affect the economy or the business operations of companies in the specific geographic region, causing an adverse impact on the Fund's or the Underlying Fund's investments in, or which are exposed to, the affected region. 
High Portfolio Turnover Risk. High portfolio turnover (considered by the Fund and the Underlying Fund to mean higher than 100% annually) may result in increased transaction costs to the Fund or an Underlying Fund, including brokerage commissions, dealer mark-ups and other transaction costs on the sale of the securities and on reinvestment in other securities. 
High Yield Securities Risk. Securities that are rated below investment-grade (commonly referred to as “junk bonds,” which may include those bonds rated below “BBB-” by S&P Global Ratings and Fitch Ratings, Inc. (“Fitch”) or below “Baa3” by Moody's Investors Service, Inc. (“Moody's”)), or are unrated, may be deemed speculative, may involve greater levels of risk than higher-rated securities of similar maturity and may be more likely to default. 
Income Risk. The Fund's income may decline when yields fall or written option 
premiums decline. This decline can occur because the Underlying Fund may subsequently invest in lower-yielding bonds as bonds in its portfolio mature, are near maturity or are called, bonds in the Underlying Fund's index are substituted, or the Underlying Fund otherwise needs to purchase additional bonds. Option premiums may fall due to changes in market conditions. 
Index-Related Risk. 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. Market disruptions and regulatory restrictions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track the Underlying Index. Errors in index data, index computations or the construction of the Underlying Index in accordance with its methodology may occur from time to time and may not be identified and corrected by the Index Provider for a period of time or at all, which may have an adverse impact on the Fund and its shareholders. Because the Index Provider is relatively new to the creation of securities indexes, there may be a greater risk that index errors will not be detected as quickly as they might be in the case of an index maintained by a long-standing index provider. Unusual market conditions may cause the Index Provider to postpone a scheduled rebalance, which could cause the Underlying Index to vary from its normal or expected composition. 
Infectious Illness Risk. An outbreak of an infectious respiratory illness, COVID-19, caused by a novel coronavirus has resulted in travel restrictions, disruption of healthcare systems, prolonged quarantines, cancellations, supply chain 
disruptions, lower consumer demand, layoffs, ratings downgrades, defaults and other significant economic impacts. Certain markets have experienced temporary closures, extreme volatility, severe losses, reduced liquidity and increased trading costs. These events will have an impact on the Fund and its investments and could impact the Fund’s ability to purchase or sell securities or cause elevated tracking error and increased premiums or discounts to the Fund's NAV. Other infectious illness outbreaks in the future may result in similar impacts. 
Interest Rate Risk. During periods of very low or negative interest rates, the Underlying Fund may be unable to maintain positive returns or pay dividends to shareholders. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, result in heightened market volatility and detract from the Underlying Fund’s performance to the extent the Underlying Fund is exposed to such interest rates. Additionally, under certain market conditions in which interest rates are low and the market prices for portfolio securities have increased, the Underlying Fund may have a very low or even negative yield. A low or negative yield would cause the Underlying Fund to lose money in certain conditions and over certain time periods. An increase in interest rates will generally cause the value of fixed income securities held by the Underlying Fund to decline, may lead to heightened volatility in the fixed-income markets and may adversely affect the liquidity of certain investments, including those held by the Fund or the Underlying Fund. 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 Underlying Fund to the extent that it invests in floating rate debt securities. The historically low interest rate environment in recent years heightens the risks associated with rising interest rates. 
Investment in the Underlying Fund Risk. The Fund expects to invest a substantial portion of its assets in the Underlying Fund, so the Fund’s investment performance is likely to be directly related to the performance of the Underlying Fund. The Fund’s NAV will change with changes in the value of the Underlying Fund and other investments based on their market valuations. An investment in the Fund will entail more costs and expenses than a direct investment in the Underlying Fund. 
As the Fund’s allocation to the Underlying Fund changes from time to time, or to the extent that the total annual fund operating expenses of the Underlying Fund change, the weighted average operating expenses borne by the Fund may increase or decrease. 
Through its investment in the Underlying Fund, the Fund is exposed to Management Risk, Market Risk, and Market Trading Risk, among other risks. 
Issuer Risk. The performance of the Fund depends on the performance of individual securities to which the Fund or the Underlying Fund has exposure. The Fund may be adversely affected if an issuer of underlying securities held 
by the Fund or Underlying Fund is unable or unwilling to repay principal or interest when due. Changes in the financial condition or credit rating of an issuer of those securities may cause the value of the securities to decline. 
Large Shareholder and Large-Scale Redemption Risk. Certain shareholders, including an Authorized Participant, a third-party investor, the Fund’s adviser or an affiliate of the Fund’s adviser, a market maker, or another entity, may from time to time own or manage a substantial amount of Fund shares, or may invest in the Fund and hold their investment for a limited period of time. There can be no assurance that any large shareholder or large group of shareholders would not redeem their investment. Redemptions of a large number of Fund shares could require the Fund to dispose of assets to meet the redemption requests, which can accelerate the realization of taxable income and/or capital gains and cause the Fund to make taxable distributions to its shareholders earlier than the Fund otherwise would have. In addition, under certain circumstances, non-redeeming shareholders may be treated as receiving a disproportionately large taxable distribution during or with respect to such year. In some circumstances, the Fund may hold a relatively large proportion of its assets in cash in anticipation of large redemptions, diluting its investment returns. These large redemptions may also force the Fund to sell portfolio securities when it might not otherwise do so, which may negatively impact the Fund’s NAV, increase the Fund’s brokerage costs and/or have a material effect on the market price of the Fund shares. 
Management Risk. As the Fund will not fully replicate the Underlying Index, it is subject to the risk that BFA's investment strategy may not produce the intended results. The Fund is also subject to the risk that the investment strategy of the Underlying Fund may not produce the intended results. 
Market Risk. The Fund and the Underlying 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, the spread of infectious illness or other public health issues, recessions, or other events could have a significant impact on the Fund, the Underlying Fund and their investments and could result in increased premiums or discounts to the Fund’s or Underlying Fund's NAV. 
Market Trading Risk. The Fund and the Underlying Fund face numerous market trading risks, including the potential lack of an active market for their shares, losses from trading in secondary markets, periods of high volatility and disruptions in the creation/redemption process. ANY OF THESE FACTORS, AMONG OTHERS, MAY LEAD TO THE FUND'S AND THE UNDERLYING FUND'S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV. 
Operational Risk. The Fund and the Underlying Fund are 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 or the Underlying Fund's service providers, counterparties or other third parties, failed or inadequate processes and technology or systems failures. The 
Fund, the Underlying 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. 
Passive Investment Risk. The Fund and the Underlying Fund are not actively managed, and BFA generally does not attempt to take defensive positions under any market conditions, including declining markets. 
Privately Issued Securities Risk. The Fund or the Underlying Fund will invest in privately issued securities, including those that are normally purchased pursuant to Rule 144A or Regulation S promulgated under the Securities Act of 1933, as amended (“1933 Act”). Privately issued securities are securities that have not been registered under the 1933 Act and as a result may be subject to legal restrictions on resale. Privately issued securities are generally not traded on established markets. As a result of the absence of a public trading market, privately issued securities may be deemed to be illiquid investments, may be more difficult to value than publicly traded securities and may be subject to wide fluctuations in value. Delay or difficulty in selling such securities may result in a loss to the Fund. 
Risk of Investing in the U.S. 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 or the Underlying Fund has exposure. 
Security Risk. Some countries and regions in which the Fund invests have experienced security concerns, such as 
terrorism and strained international relations. Incidents involving a country's or region's security may cause uncertainty in its markets and may adversely affect its economy and the Fund's or the Underlying Fund's investments. 
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 the Fund does not meet certain conditions of the listing exchange. Any resulting liquidation of the Fund could cause the Fund to incur elevated transaction costs for the Fund and negative tax consequences for its shareholders. 
Tax Risk. The tax rules and limitations that apply to the Fund will cause some or all of its income and gain to be taxable as ordinary income or at ordinary income rates, may accelerate its recognition of income and gain, and may defer its use of losses, all of which are expected to have negative tax consequences for the Fund and Fund investors. Because the assets comprising the Underlying Index and held by the Underlying Fund will not consist of stock, ordinary dividends from the Fund will not be eligible for the reduced rates applicable to “qualified dividend income” or eligible for the dividends-received deduction. The Fund expects that its ownership of shares of the Underlying Fund and sale of call options thereon generally will constitute “straddles” (offsetting positions with respect to personal property) under section 1092 of the Internal Revenue Code. The straddle rules generally do not apply if all the straddle’s offsetting positions consist of “qualified covered call options” and the stock to be purchased under the options, and the 
straddle is not part of a larger straddle. Unlike certain other funds that utilize covered call strategies, the Fund does not anticipate that this exception will be available because, as a general matter, the call options it writes are not expected to be treated as “qualified covered call options.” The straddle rules usually will terminate the Fund’s holding periods for its shares of the Underlying Fund that become part of a straddle before the long-term capital gain holding period (more than one year) has been reached, which is expected to eliminate the Fund’s ability to recognize long-term capital gains from a sale or other disposition of such shares. The straddle rules also usually will defer recognition of realized losses and require the capitalization of certain interest expenses and carrying charges. Similarly, “wash sale” rules may apply to defer the recognition of loss by the Fund from the disposition of stock or securities at a loss in a case in which identical or substantially identical stock or securities (or an option to acquire such property) is or has been acquired within a prescribed period. As a result of the foregoing, an investor may be subject to significantly greater amounts of tax as a result of the investment than would apply to an investment in a fund engaged in a different investment strategy. 
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 because of differences between the securities and other instruments held in the Fund’s portfolio and those included in the Underlying Index, pricing differences (including, as applicable, differences between a security’s price 
at the local market close and the Fund's or an Underlying Fund's valuation of a security at the time of calculation of the Fund's or Underlying Fund's NAV, respectively), transaction costs incurred by the Fund, the Fund’s holding of uninvested cash, differences in timing of the accrual of or the valuation of distributions, the requirements to maintain pass-through tax treatment, portfolio transactions carried out to minimize the distribution of capital gains to shareholders, acceptance of custom baskets, changes to the Underlying Index, the effect the Fund’s transactions would have on the market for the securities in the Underlying Index or the costs to the Fund of complying with various new or existing regulatory requirements, among other reasons. This risk may be heightened during times of increased market volatility or other unusual market conditions. Tracking error also may result because the Fund incurs fees and expenses, while the Underlying Index does not. INDEX ETFs THAT TRACK INDICES WITH SIGNIFICANT WEIGHT IN OPTIONS MAY EXPERIENCE HIGHER TRACKING ERROR THAN OTHER INDEX ETFs THAT DO NOT TRACK SUCH INDICES. 
Valuation Risk. The price the Fund or the Underlying Fund could receive upon the sale of a security or other asset may differ from the Fund's or the Underlying Fund's valuation of the security or other asset and from the value used by its underlying index, particularly for securities or other assets that trade in low volume or volatile markets or that are valued using a fair value methodology as a result of trade suspensions or for other reasons. In addition, the value of the securities or 
other assets in the Fund's or the Underlying Fund's portfolio may change on days or during time periods when shareholders will not be able to purchase or sell the Fund's or the Underlying Fund's shares. Authorized Participants who purchase or redeem Fund shares on days when the Fund or the Underlying Fund is holding fair-valued securities may receive fewer or more shares, or lower or higher 
redemption proceeds, than they would have received had the Fund or the Underlying Fund not fair-valued securities or used a different valuation methodology. The Fund’s or the Underlying Fund's ability to value investments may be impacted by technological issues or errors by pricing services or other third-party service providers. 
Risk Lose Money [Text] rr_RiskLoseMoney 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.
Bar Chart and Performance Table [Heading] rr_BarChartAndPerformanceTableHeading Performance Information
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock
As of the date of the Prospectus, the Fund has not commenced operations and therefore has no performance information to report.
Performance One Year or Less [Text] rr_PerformanceOneYearOrLess As of the date of the Prospectus, the Fund has not commenced operations and therefore has no performance information to report.
iShares High Yield Corporate Bond BuyWrite Strategy ETF | iShares High Yield Corporate Bond BuyWrite Strategy ETF  
Risk/Return: rr_RiskReturnAbstract  
Management Fees rr_ManagementFeesOverAssets 0.70%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses rr_OtherExpensesOverAssets none [1]
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.49%
Total Annual Fund Operating Expenses rr_ExpensesOverAssets 1.19%
Fee Waiver rr_FeeWaiverOrReimbursementOverAssets (0.50%)
Total Annual Fund Operating Expenses After Fee Waiver rr_NetExpensesOverAssets 0.69%
1 Year rr_ExpenseExampleYear01 $ 70
3 Years rr_ExpenseExampleYear03 $ 221
[1] The amount rounded to 0.00%.