S000057342 [Member] Investment Strategy - iShares Investment Grade Systematic Bond ETF	Feb. 28, 2025
Prospectus [Line Items]
Strategy [Heading]	Principal Investment Strategies
Strategy Narrative [Text Block]	The Fund seeks to track the investment results of the BlackRock Investment Grade Systematic Bond Index (the “Underlying Index”), which consists of U.S. dollar-denominated, investment-grade (as determined by BlackRock Index Services, LLC (the “Index Provider”)) corporate bonds. Component securities include publicly-issued debt of U.S. corporate issuers and U.S. dollar-denominated, publicly issued debt of non-U.S. corporate issuers. As of February 28, 2025, a significant portion of the Underlying Index is represented by securities of companies in the financials industry or sector. The components of the Underlying Index are likely to change over time. The securities in the Underlying Index must have $500 million or more current face amount outstanding, and have at least one year to final maturity, regardless of optionality, at time of rebalance. In addition, the securities in the Underlying Index must be denominated in U.S. dollars and have a fixed-rate, although they can carry a coupon that steps-up (i.e., changes according to a predetermined schedule). Fixed-to-Float bonds are eligible, provided that there is a minimum of 12 months until the transition date to the floating rate period. Component securities must be rated investment-grade, which is Baa3 or higher by Moody’s Investors Service, Inc. (“Moody's”) or BBB- or higher by Standard & Poor's® Global Ratings, a subsidiary of S&P Global (“S&P Global Ratings”) or Fitch Ratings, Inc. (“Fitch”). Eligibility for the Underlying Index is determined by the middle of the three available ratings. When a rating from only two agencies is available, the lower rating is used. When a rating from only one agency is available, that rating is used to determine eligibility for the Underlying Index. The Underlying Index determines constituent weights based on a proprietary methodology which first aims to systematically screen out certain bonds with the highest probability of default (a measure of credit quality) and then optimizes to improve risk-adjusted returns by weighting more heavily to bonds with attractive default-adjusted spreads (a measure of value) while mitigating portfolio risks and limiting turnover. This methodology, unlike the methodologies used by traditional market-value-weighted bond indexes, selects a portion of the component bonds from the broader universe of investment-grade bonds based on application of analytics measuring the probability of default. The resulting grouping of bonds is referred to as “enhanced,” by comparison to other groupings of investment-grade bonds, because the Underlying Index seeks to provide superior risk-adjusted and total returns over longer periods of time than a comparable market-value-weighted index. Key investment characteristics such as duration are constrained to be within a specified range of a broader market-value-weighted investment-grade bond universe. The Underlying Index is rebalanced on the last business day of each month to reflect changes in eligibility, credit quality and valuation. Investment-grade bonds included in the Underlying Index, like all investment-grade debt, continue to be subject to a number of risks, including the risk of an issuer default and volatility of the market value of the bonds. 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 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 fixed income securities of the types included in the Underlying Index that BFA believes will help the Fund track the Underlying Index. 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 as well as in fixed income securities other than the types included in the Underlying Index, but which 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. 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 sponsored by the Index Provider, an affiliated person of the Fund and of BFA, the Fund's investment adviser. 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), repurchase agreements collateralized by U.S. government securities, and securities of state or municipal governments and their political subdivisions are not considered to be issued by members of any industry.
Strategy Portfolio Concentration [Text]	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), repurchase agreements collateralized by U.S. government securities, and securities of state or municipal governments and their political subdivisions are not considered to be issued by members of any industry.

The Fund seeks to track the investment results of the BlackRock Investment Grade Systematic Bond Index (the “Underlying Index”), which consists of U.S. dollar-denominated, investment-grade (as determined by BlackRock Index Services, LLC (the “Index Provider”)) corporate bonds. Component securities include publicly-issued debt of U.S. corporate issuers and U.S. dollar-denominated, publicly issued debt of non-U.S. corporate issuers. As of February 28, 2025, a significant portion of the Underlying Index is represented by securities of companies in the financials industry or sector. The components of the Underlying Index are likely to change over time.

The securities in the Underlying Index must have $500 million or more current face amount outstanding, and have at least one year to final maturity, regardless of optionality, at time of rebalance. In addition, the securities in the Underlying Index must be denominated in U.S. dollars and have a fixed-rate, although they can carry a coupon that steps-up (i.e., changes according to a predetermined schedule). Fixed-to-Float bonds are eligible, provided that there is a minimum of 12 months until the transition date to the floating rate period. Component securities must be rated investment-grade, which is Baa3 or higher by Moody’s Investors Service, Inc. (“Moody's”) or BBB- or higher by Standard & Poor's® Global Ratings, a subsidiary of S&P Global (“S&P Global Ratings”) or Fitch Ratings, Inc. (“Fitch”). Eligibility for the Underlying Index is determined by the middle of the three available ratings. When a rating from only two agencies is available, the lower rating is used. When a rating from only one agency is available, that rating is used to determine eligibility for the Underlying Index.

The Underlying Index determines constituent weights based on a proprietary methodology which first aims to systematically screen out certain bonds with the highest probability of default (a measure of credit quality) and then optimizes to improve risk-adjusted returns by weighting more heavily to bonds with attractive default-adjusted spreads (a measure of value) while mitigating portfolio risks and limiting turnover. This methodology, unlike the methodologies used by traditional market-value-weighted bond indexes, selects a portion of the component bonds from the broader universe of investment-grade bonds based on application of analytics measuring the probability of default. The resulting grouping of bonds is referred to as “enhanced,” by comparison to other groupings of investment-grade bonds, because the Underlying Index seeks to provide superior risk-adjusted and total returns over longer periods of time than a comparable market-value-weighted index. Key investment characteristics such as duration are constrained to be within a specified range of a broader market-value-weighted investment-grade bond universe. The Underlying Index is rebalanced on the last business day of each month to reflect changes in eligibility,

credit quality and valuation. Investment-grade bonds included in the Underlying Index, like all investment-grade debt, continue to be subject to a number of risks, including the risk of an issuer default and volatility of the market value of the bonds.

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 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 fixed income securities of the types included in the Underlying Index that BFA believes will help the Fund track the Underlying Index. 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 as well as in fixed income securities other than the types included in the Underlying Index, but which 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.

The Underlying Index is sponsored by the Index Provider, an affiliated person of the Fund and of BFA, the Fund's investment adviser. 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), repurchase agreements collateralized by U.S. government securities, and