Class K [Member] Expense Example - Class K - BlackRock Mid-Cap Value Fund - Class K	Apr. 30, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 72
Expense Example, with Redemption, 3 Years	228
Expense Example, with Redemption, 5 Years	399
Expense Example, with Redemption, 10 Years	$ 893

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