Class K [Member] Expense Example - Class K - BLACKROCK GLOBAL ALLOCATION FUND, INC. - Class K	Apr. 30, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 79
Expense Example, with Redemption, 3 Years	252
Expense Example, with Redemption, 5 Years	441
Expense Example, with Redemption, 10 Years	$ 987

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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