v3.26.1
Investor A C Institutional and Class R [Member] Expense Example - Investor A, C, Institutional and Class R - BlackRock LifePath Dynamic Retirement Fund
Dec. 31, 2025
USD ($)
Investor A Shares  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year $ 606
Expense Example, with Redemption, 3 Years 816
Expense Example, with Redemption, 5 Years 1,042
Expense Example, with Redemption, 10 Years 1,692
Investor C Shares  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 262
Expense Example, with Redemption, 3 Years 540
Expense Example, with Redemption, 5 Years 943
Expense Example, with Redemption, 10 Years 1,871
Institutional Shares  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 60
Expense Example, with Redemption, 3 Years 228
Expense Example, with Redemption, 5 Years 410
Expense Example, with Redemption, 10 Years 937
Class R Shares  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 106
Expense Example, with Redemption, 3 Years 369
Expense Example, with Redemption, 5 Years 653
Expense Example, with Redemption, 10 Years $ 1,461