Objective, Primary [Text Block]

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Risk/Return [Heading]

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Fund OverviewKey Facts About BlackRock Advantage Small Cap Growth Fund

Objective [Heading]

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Investment Objective

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The investment objective of BlackRock Advantage Small Cap Growth Fund (“Advantage Small Cap Growth”or the “Fund”), a series of BlackRock FundsSM (the “Trust”), is to seek long-term capital growth.

Expense [Heading]

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Fees and Expenses of the Fund

Expense Narrative [Text Block]

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This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to your financial professional or your selected securities dealer, broker, investment adviser, service provider or industry professional (including BlackRock Advisors, LLC (“BlackRock”) and its affiliates) (each, a “Financial Intermediary”), which are not reflected in the table and example below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in the fund complex advised by BlackRock or its affiliates. More information about these and other discounts is available from your Financial Intermediary and in the “Details About the Share Classes” and the “Intermediary-Defined Sales Charge Waiver Policies” sections on pages 23 and A-1, respectively, of the Fund’s prospectus and in the “Purchase of Shares” section on page II-94 of Part II of the Fund’s Statement of Additional Information.

Shareholder Fees Caption [Text]

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Shareholder Fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

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Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

June 30, 2026

Portfolio Turnover [Heading]

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Portfolio Turnover:

Portfolio Turnover [Text Block]

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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 higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 148% of the average value of its portfolio.

Portfolio Turnover, Rate

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148.00%

Expenses Deferred Charges [Text Block]

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A contingent deferred sales charge (“CDSC”) of 1.00% is assessed on certain redemptions of Investor A Shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase as part of an investment of $1,000,000 or more.

Expense Breakpoint Discounts [Text]

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You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in the fund complex advised by BlackRock or its affiliates.

Expense Breakpoint, Minimum Investment Required [Amount]

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$ 25,000

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

The Total Annual Fund Operating Expenses does not correlate to the ratios of expenses to average net assets given in the Fund’s most recent annual financial statements and additional information, which does not include Acquired Fund Fees and Expenses.

Expense Example [Heading]

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Example:

Expense Example Narrative [Text Block]

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This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’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]

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Principal Investment Strategies of the Fund

Strategy Narrative [Text Block]

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Under normal circumstances, the Fund will invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in small cap growth equity securities of U.S. issuers and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. Equity securities consist primarily of common stock, preferred stock and securities or other instruments whose price is linked to the value of common stock, such as derivatives. The Fund seeks to buy primarily common stock but also can invest in preferred stock and other equity securities. The Fund may also purchase convertible securities. The Fund management team focuses on small capitalization companies that Fund management believes have above average prospects for earnings growth. For purposes of the Fund’s 80% policy, small cap growth equity securities are equity securities that (i) at the time of purchase have a market capitalization within the range of companies included in the Russell 2000® Growth Index (the “Russell 2000 Growth Index”) and (ii) are included within at least one growth index, as determined by BlackRock (the “Growth Indices”). Currently, such Growth Indices are the Russell 3000® Growth Index, the S&P Composite 1500® Growth Index and the MSCI World Growth Index. The Russell 2000 Growth Index is an index that measures the performance of the small-cap growth segment of the U.S. equity universe, with companies that have market capitalizations between approximately $6.91 million and $14.72 billion as of December 31, 2024.

From time to time the Fund may invest in shares of companies through “new issues” or initial public offerings (“IPOs”).

The Fund may use derivatives, including options, warrants, futures, swaps and forward contracts both to seek to increase the return of the Fund and to hedge (or protect) the value of its assets against adverse movements in currency exchange rates, interest rates and movements in the securities markets. In order to manage cash flows into or out of the Fund effectively, the Fund may buy and sell financial futures contracts or options on such contracts. Derivatives are financial instruments whose value is derived from another security, a commodity (such as oil or gas), a currency or an index, including but not limited to the Growth Indices. The use of options, futures, swaps and forward contracts can be effective in protecting or enhancing the value of the Fund’s assets.

The Fund will seek to pursue its investment objective by investing in small cap growth equity securities in a disciplined manner using proprietary return forecast models. These forecast models are designed to identify aspects of mispricing across stocks, which the Fund can seek to capture by over- and under-weighting particular equities while seeking to control incremental risk.

The Fund also may use indexed or inverse securities.

Risk [Heading]

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Principal Risks of Investing in the Fund

Bar Chart and Performance Table [Heading]

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Performance Information

Performance Narrative [Text Block]

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The information shows you how Advantage Small Cap Growth’s performance has varied year by year and provides some indication of the risks of investing in the Fund. Class R Shares commenced operations on March 2, 2018. As a result, the returns shown below for Class R Shares prior to March 2, 2018 are those of the Fund’s Institutional Shares, adjusted to reflect the fees and expenses applicable to Class R Shares. The table compares the Fund’s performance to that of the Russell 3000® Index and the Russell 2000 Growth Index. The Russell 2000 Growth Index is relevant to the Fund because it has characteristics similar to the Fund’s investment strategy. To the extent that dividends and distributions have been paid by the Fund, the performance information for the Fund in the chart and table assumes reinvestment of the dividends and distributions. As with all such investments, past performance (before and after taxes) is not an indication of future results. Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown. However, the table includes all applicable fees and sales charges. If BlackRock and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund’s returns would have been lower. Updated information on the Fund’s performance, including its current net asset value, can be obtained by visiting www.blackrock.com or can be obtained by phone at (800) 882-0052.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The information shows you how Advantage Small Cap Growth’s performance has varied year by year and provides some indication of the risks of investing in the Fund.

Performance Additional Market Index [Text]

rr_PerformanceAdditionalMarketIndex

The table compares the Fund’s performance to that of the Russell 3000® Index and the Russell 2000 Growth Index. The Russell 2000 Growth Index is relevant to the Fund because it has characteristics similar to the Fund’s investment strategy.

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

(800) 882-0052

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

www.blackrock.com

Performance Past Does Not Indicate Future [Text]

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As with all such investments, past performance (before and after taxes) is not an indication of future results.

Bar Chart [Heading]

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Investor A Shares ANNUAL TOTAL RETURNS BlackRock Advantage Small Cap Growth Fund As of 12/31

Bar Chart Does Not Reflect Sales Loads [Text]

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Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown.

Bar Chart Closing [Text Block]

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During the ten-year period shown in the bar chart, the highest return for a quarter was 30.82% (quarter ended June 30, 2020) and the lowest return for a quarter was -26.19% (quarter ended March 31, 2020).

Performance Table Heading

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For the periods ended 12/31/24Average Annual Total Returns

Performance Table Does Reflect Sales Loads

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However, the table includes all applicable fees and sales charges.

Performance Table Uses Highest Federal Rate

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After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

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Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

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After-tax returns are shown for Investor A Shares only, and the after-tax returns for Institutional and Class R Shares will vary.

Performance Table Narrative

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After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Investor A Shares only, and the after-tax returns for Institutional and Class R Shares will vary.

Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Risk Lose Money [Member]

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Equity Securities Risk [Member]

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You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Small Cap and Emerging Growth Securities Risk [Member]

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◼

Equity Securities Risk — Stock markets are volatile. The price of equity securities fluctuates based on changes in a company’s financial condition and overall market and economic conditions.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Investment Style Risk [Member]

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◼

Small Cap and Emerging Growth Securities Risk — Small cap or emerging growth companies may have limited product lines or markets. They may be less financially secure than larger, more established companies. They may depend on a more limited management group than larger capitalized companies.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Model Risk [Member]

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◼

Investment Style Risk — Under certain market conditions, growth investments have performed better during the later stages of economic expansion. Therefore, this investment style may over time go in and out of favor. At times when the investment style used by the Fund is out of favor, the Fund may underperform other equity funds that use different investment styles.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Convertible Securities Risk [Member]

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◼

Model Risk — The Fund seeks to pursue its investment objective by using proprietary models that incorporate quantitative analysis. Investments selected using these models may perform differently than as forecasted due to the factors incorporated into the models and the weighting of each factor, changes from historical trends, and issues in the construction and implementation of the models (including, but not limited to, software issues and other technological issues). There is no guarantee that BlackRock’s use of these models will result in effective investment decisions for the Fund.

The information and data used in the models may be supplied by third parties. Inaccurate or incomplete data may limit the effectiveness of the models. In addition, some of the data that BlackRock uses may be historical data, which may not accurately predict future market movement. There is a risk that the models will not be successful in selecting investments or in determining the weighting of investment positions that will enable the Fund to achieve its investment objective.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Derivatives Risks [Member]

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◼

Convertible Securities Risk — The market value of a convertible security performs like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest, principal or dividends when due, and their market value may change based on changes in the issuer’s credit rating or the market’s perception of the issuer’s creditworthiness. Since it derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock, including the potential for increased volatility in the price of the convertible security.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | High Portfolio Turnover Risk [Member]

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◼

Derivatives Risk — The Fund’s use of derivatives may increase its costs, reduce the Fund’s returns and/or increase volatility. Derivatives involve significant risks, including:

Leverage Risk — The Fund’s use of derivatives can magnify the Fund’s gains and losses. Relatively small market movements may result in large changes in the value of a derivatives position and can result in losses that greatly exceed the amount originally invested.

Market Risk — Some derivatives are more sensitive to interest rate changes and market price fluctuations than other securities. The Fund could also suffer losses related to its derivatives positions as a result of unanticipated market movements, which losses are potentially unlimited. Finally, BlackRock may not be able to predict correctly the direction of securities prices, interest rates and other economic factors, which could cause the Fund’s derivatives positions to lose value.

Counterparty Risk — Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will be unable or unwilling to fulfill its contractual obligation, and the related risks of having concentrated exposure to such a counterparty.

Illiquidity Risk — The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately.

Operational Risk — The use of derivatives includes the risk of potential operational issues, including documentation issues, settlement issues, systems failures, inadequate controls and human error.

Legal Risk — The risk of insufficient documentation, insufficient capacity or authority of counterparty, or legality or enforceability of a contract.

Volatility and Correlation Risk — Volatility is defined as the characteristic of a security, an index or a market to fluctuate significantly in price within a short time period. A risk of the Fund’s use of derivatives is that the fluctuations in their values may not correlate with the overall securities markets.

Valuation Risk — Valuation for derivatives may not be readily available in the market. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them.

Hedging Risk — Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Fund’s hedging transactions will be effective. The use of hedging may result in certain adverse tax consequences.

Tax Risk — Certain aspects of the tax treatment of derivative instruments, including swap agreements and commodity-linked derivative instruments, are currently unclear and may be affected by changes in legislation, regulations or other legally binding authority. Such treatment may be less favorable than that given to a direct investment in an underlying asset and may adversely affect the timing, character and amount of income the Fund realizes from its investments.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Indexed and Inverse Securities Risk [Member]

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◼

High Portfolio Turnover Risk — The Fund may engage in active and frequent trading of its portfolio securities. High portfolio turnover (more than 100%) may result in increased transaction costs to the Fund, including brokerage commissions, dealer mark-ups and other transaction costs on the sale of the securities and on reinvestment in other securities. The sale of Fund portfolio securities may result in the realization and/or distribution to shareholders of higher capital gains or losses as compared to a fund with less active trading policies. These effects of higher than normal portfolio turnover may adversely affect Fund performance.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Leverage Risk [Member]

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◼

Indexed and Inverse Securities Risk — Indexed and inverse securities provide a potential return based on a particular index of value or interest rates. The Fund’s return on these securities will be subject to risk with respect to the value of the particular index. These securities are subject to leverage risk and correlation risk. Certain indexed and inverse securities have greater sensitivity to changes in interest rates or index levels than other securities, and the Fund’s investment in such instruments may decline significantly in value if interest rates or index levels move in a way Fund management does not anticipate.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Market Risk and Selection Risk [Member]

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Leverage Risk — Some transactions may give rise to a form of economic leverage. These transactions may include, among others, derivatives, and may expose the Fund to greater risk and increase its costs. The use of leverage may cause the Fund to liquidate portfolio positions when it may not be advantageous to do so to satisfy its obligations or to meet the applicable requirements of the Investment Company Act of 1940, as amended, and the rules thereunder. Increases and decreases in the value of the Fund’s portfolio will be magnified when the Fund uses leverage.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | New Issues Risks [Member]

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◼

Market Risk and Selection Risk — Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a security or other asset may decline due to changes in general market conditions, economic trends or events that are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its investments. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. The Fund seeks to pursue its investment objective by using proprietary models that incorporate quantitative analysis and is subject to “Model Risk” as described above. This means you may lose money.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Preferred Securities Risk [Member]

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◼

“New Issues” Risk — “New issues” are IPOs of equity securities. Securities issued in IPOs have no trading history, and information about the companies may be available for very limited periods. In addition, the prices of securities sold in IPOs may be highly volatile or may decline shortly after the IPO.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Risk of Investing in the United States [Member]

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◼

Preferred Securities Risk — Preferred securities may pay fixed or adjustable rates of return. Preferred securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. Preferred securities of smaller companies may be more vulnerable to adverse developments than preferred securities of larger companies.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Warrants Risk [Member]

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◼

Risk of Investing in the United States — Certain changes in the U.S. economy, such as when the U.S. economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.

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Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Investor A Shares

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◼

Warrants Risk — If the price of the underlying stock does not rise above the exercise price before the warrant expires, the warrant generally expires without any value and the Fund will lose any amount it paid for the warrant. Thus, investments in warrants may involve substantially more risk than investments in common stock. Warrants may trade in the same markets as their underlying stock; however, the price of the warrant does not necessarily move with the price of the underlying stock.

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

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5.25%

Maximum Deferred Sales Charge (Load) (as a percentage of offering price or redemption proceeds, whichever is lower)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

^[1]

Management Fee

rr_ManagementFeesOverAssets

0.45%

^[2]

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.34%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.04%

Fee Waivers and/or Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.29%)

^[2],[3]

Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements

rr_NetExpensesOverAssets

0.75%

^[2],[3]

rr_ExpenseExampleYear01

$ 598

3 Years

rr_ExpenseExampleYear03

811

rr_ExpenseExampleYear05

1,042

Highest Quarterly Return, Label

rr_ExpenseExampleYear10

$ 1,704

2015

rr_AnnualReturn2015

(3.88%)

2016

rr_AnnualReturn2016

13.06%

2017

rr_AnnualReturn2017

14.62%

2018

rr_AnnualReturn2018

(5.29%)

2019

rr_AnnualReturn2019

33.45%

2020

rr_AnnualReturn2020

33.13%

2021

rr_AnnualReturn2021

3.32%

2022

rr_AnnualReturn2022

(25.18%)

2023

rr_AnnualReturn2023

18.47%

2024

rr_AnnualReturn2024

13.77%

rr_HighestQuarterlyReturnLabel

highest return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2020

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

30.82%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

lowest return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Mar. 31, 2020

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(26.19%)

rr_AverageAnnualReturnYear01

7.80%

rr_AverageAnnualReturnYear05

5.62%

Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Institutional Shares

rr_AverageAnnualReturnYear10

7.54%

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

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rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as a percentage of offering price or redemption proceeds, whichever is lower)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Management Fee

rr_ManagementFeesOverAssets

0.45%

^[2]

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.34%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.79%

Fee Waivers and/or Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.29%)

^[2],[3]

Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements

rr_NetExpensesOverAssets

0.50%

^[2],[3]

rr_ExpenseExampleYear01

$ 51

3 Years

rr_ExpenseExampleYear03

223

rr_ExpenseExampleYear05

410

rr_ExpenseExampleYear10

$ 951

rr_AverageAnnualReturnYear01

14.07%

rr_AverageAnnualReturnYear05

7.03%

Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Class R Shares

rr_AverageAnnualReturnYear10

8.41%

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

rr_RiskReturnAbstract

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as a percentage of offering price or redemption proceeds, whichever is lower)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Management Fee

rr_ManagementFeesOverAssets

0.45%

^[2]

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.40%

^[4]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.35%

^[4]

Fee Waivers and/or Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.35%)

^[2],[3]

Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements

rr_NetExpensesOverAssets

1.00%

^[2],[3]

rr_ExpenseExampleYear01

$ 102

3 Years

rr_ExpenseExampleYear03

393

rr_ExpenseExampleYear05

706

rr_ExpenseExampleYear10

$ 1,593

rr_AverageAnnualReturnYear01

13.55%

rr_AverageAnnualReturnYear05

6.50%

Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Return After Taxes on Distributions | Investor A Shares

rr_AverageAnnualReturnYear10

7.87%

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

7.75%

rr_AverageAnnualReturnYear05

3.62%

Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Return After Taxes on Distributions and Sale of Fund Shares | Investor A Shares

rr_AverageAnnualReturnYear10

5.06%

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

4.65%

rr_AverageAnnualReturnYear05

3.91%

Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Russell 3000® Index (Reflects no deduction for fees, expenses or taxes)

rr_AverageAnnualReturnYear10

5.28%

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

23.81%

^[5]

rr_AverageAnnualReturnYear05

13.86%

^[5]

Investor A, Institutional and Class R | BLACKROCK ADVANTAGE SMALL CAP GROWTH FUND | Russell 2000® Growth Index (Reflects no deduction for fees, expenses or taxes)

rr_AverageAnnualReturnYear10

12.55%

^[5]

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

15.15%

rr_AverageAnnualReturnYear05

6.86%