Investor P [Member] Expense Example - Investor P - BlackRock LifePath Index 2060 Fund - Investor P Shares	Dec. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 563
Expense Example, with Redemption, 3 Years	652
Expense Example, with Redemption, 5 Years	750
Expense Example, with Redemption, 10 Years	$ 1,035

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