Investor A C Institutional and Class R [Member] Investment Strategy - Investor A, C, Institutional and Class R - BLACKROCK GLOBAL ALLOCATION FUND, INC.	Apr. 30, 2025
Prospectus [Line Items]
Strategy [Heading]	Principal Investment Strategies of the Fund
Strategy Narrative [Text Block]	The Fund invests in a portfolio of equity, debt and money market securities. Generally, the Fund’s portfolio will include both equity and debt securities. Equity securities include common stock, preferred stock, rights and warrants or securities or other instruments whose price is linked to the value of common stock. At any given time, however, the Fund may emphasize either debt securities or equity securities. In selecting equity investments, the Fund mainly seeks securities that Fund management believes are undervalued. The Fund may buy debt securities of varying maturities, debt securities paying a fixed or fluctuating rate of interest, and debt securities of any kind, including, by way of example, securities issued or guaranteed by the U.S. Government or its agencies or instrumentalities, by foreign governments or international agencies or supranational entities, or by domestic or foreign private issuers, debt securities convertible into equity securities, inflation-indexed bonds, structured notes, credit-linked notes, loan assignments and loan participations. In addition, the Fund may invest up to 35% of its total assets in “junk bonds,” corporate loans and distressed securities. The Fund may also invest in Real Estate Investment Trusts (“REITs”) and securities related to real assets (like real estate- or precious metals-related securities) such as stock, bonds or convertible bonds issued by REITs or companies that mine precious metals. The Fund may also purchase convertible securities. When choosing investments, Fund management considers various factors, including opportunities for equity or debt investments to increase in value, expected dividends and interest rates. The Fund generally seeks diversification across markets, industries and issuers as one of its strategies to reduce volatility. The Fund has no geographic limits on where it may invest. This flexibility allows Fund management to look for investments in markets around the world, including emerging markets, that it believes will provide the best asset allocation to meet the Fund’s objective. The Fund may invest in the securities of companies of any market capitalization. Generally, the Fund may invest in the securities of corporate and governmental issuers located anywhere in the world. The Fund may emphasize foreign securities when Fund management expects these investments to outperform U.S. securities. When choosing investment markets, Fund management considers various factors, including economic and political conditions, potential for economic growth and possible changes in currency exchange rates. In addition to investing in foreign securities, the Fund actively manages its exposure to foreign currencies through the use of forward currency contracts and other currency derivatives. The Fund may own foreign cash equivalents or foreign bank deposits as part of the Fund’s investment strategy. The Fund will also invest in non-U.S. currencies. The Fund may underweight or overweight a currency based on the Fund management team’s outlook. Under normal circumstances, the Fund will allocate a substantial amount (approximately 40% or more — unless market conditions are not deemed favorable by BlackRock, in which case the Fund would invest at least 30%) of its total assets in securities of (i) foreign government issuers, (ii) issuers organized or located outside the United States, (iii) issuers which primarily trade in a market located outside the United States, or (iv) issuers doing a substantial amount of business outside the United States, which the Fund considers to be companies that derive at least 50% of their revenue or profits from business outside the United States or have at least 50% of their sales or assets outside the United States. The Fund will allocate its assets among various regions and countries including the United States (but in no less than three different countries). For temporary defensive purposes the Fund may deviate very substantially from the allocation described above. The Fund may use derivatives, including options, futures, swaps (including, but not limited to, total return swaps that may be referred to as contracts for difference) 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. The Fund may invest in indexed securities and inverse securities. The Fund may seek to provide exposure to the investment returns of real assets that trade in the commodity markets through investment in commodity-linked derivative instruments and investment vehicles such as exchange traded funds that invest exclusively in commodities and are designed to provide this exposure without direct investment in physical commodities. The Fund may also gain exposure to commodity markets by investing up to 25% of its total assets in BlackRock Cayman Global Allocation Fund I, Ltd. (the “Cayman Subsidiary”), a wholly owned subsidiary of the Fund formed in the Cayman Islands, which invests primarily in commodity-related instruments. The Cayman Subsidiary may also hold cash and invest in other instruments, including fixed income securities, either as investments or to serve as margin or collateral for the Cayman Subsidiary’s derivative positions. The Cayman Subsidiary (unlike the Fund) may invest without limitation in commodity-related instruments.

The Fund invests in a portfolio of equity, debt and money market securities. Generally, the Fund’s portfolio will include both equity and debt securities. Equity securities include common stock, preferred stock, rights and warrants or securities or other instruments whose price is linked to the value of common stock. At any given time, however, the Fund may emphasize either debt securities or equity securities. In selecting equity investments, the Fund mainly seeks securities that Fund management believes are undervalued. The Fund may buy debt securities of varying maturities, debt securities paying a fixed or fluctuating rate of interest, and debt securities of any kind, including, by way of example, securities issued or guaranteed by the U.S. Government or its agencies or instrumentalities, by foreign governments or international agencies or supranational entities, or by domestic or foreign private issuers, debt securities convertible into equity securities, inflation-indexed bonds, structured notes, credit-linked notes, loan assignments and loan participations. In addition, the Fund may invest up to 35% of its total assets in “junk bonds,” corporate loans and distressed securities. The Fund may also invest in Real Estate Investment Trusts (“REITs”) and securities related to real assets (like real estate- or precious metals-related securities) such as stock, bonds or convertible bonds issued by REITs or companies that mine precious metals. The Fund may also purchase convertible securities.

When choosing investments, Fund management considers various factors, including opportunities for equity or debt investments to increase in value, expected dividends and interest rates. The Fund generally seeks diversification across markets, industries and issuers as one of its strategies to reduce volatility. The Fund has no geographic limits on where it may invest. This flexibility allows Fund management to look for investments in markets around the world, including emerging markets, that it believes will provide the best asset allocation to meet the Fund’s objective. The Fund may invest in the securities of companies of any market capitalization.

Generally, the Fund may invest in the securities of corporate and governmental issuers located anywhere in the world. The Fund may emphasize foreign securities when Fund management expects these investments to outperform U.S. securities. When choosing investment markets, Fund management considers various factors, including economic and political conditions, potential for economic growth and possible changes in currency exchange rates. In addition to

investing in foreign securities, the Fund actively manages its exposure to foreign currencies through the use of forward currency contracts and other currency derivatives. The Fund may own foreign cash equivalents or foreign bank deposits as part of the Fund’s investment strategy. The Fund will also invest in non-U.S. currencies. The Fund may underweight or overweight a currency based on the Fund management team’s outlook.

Under normal circumstances, the Fund will allocate a substantial amount (approximately 40% or more — unless market conditions are not deemed favorable by BlackRock, in which case the Fund would invest at least 30%) of its total assets in securities of (i) foreign government issuers, (ii) issuers organized or located outside the United States, (iii) issuers which primarily trade in a market located outside the United States, or (iv) issuers doing a substantial amount of business outside the United States, which the Fund considers to be companies that derive at least 50% of their revenue or profits from business outside the United States or have at least 50% of their sales or assets outside the United States. The Fund will allocate its assets among various regions and countries including the United States (but in no less than three different countries). For temporary defensive purposes the Fund may deviate very substantially from the allocation described above.

The Fund may use derivatives, including options, futures, swaps (including, but not limited to, total return swaps that may be referred to as contracts for difference) 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. The Fund may invest in indexed securities and inverse securities.

The Fund may seek to provide exposure to the investment returns of real assets that trade in the commodity markets through investment in commodity-linked derivative instruments and investment vehicles such as exchange traded funds that invest exclusively in commodities and are designed to provide this exposure without direct investment in physical commodities. The Fund may also gain exposure to commodity markets by investing up to 25% of its total assets in BlackRock Cayman Global Allocation Fund I, Ltd. (the “Cayman Subsidiary”), a wholly owned subsidiary of the Fund formed in the Cayman Islands, which invests primarily in commodity-related instruments. The Cayman Subsidiary may also hold cash and invest in other instruments, including fixed income securities, either as investments or to serve as margin or collateral for the Cayman Subsidiary’s derivative positions. The Cayman Subsidiary (unlike the Fund) may invest without limitation in commodity-related instruments.