v3.26.1
Investor A C Institutional and Class R [Member] Expense Example - Investor A, C, Institutional and Class R - BlackRock Advantage SMID Cap Fund, Inc.
Mar. 31, 2026
USD ($)
Investor A Shares  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year $ 596
Expense Example, with Redemption, 3 Years 801
Expense Example, with Redemption, 5 Years 1,024
Expense Example, with Redemption, 10 Years 1,662
Investor C Shares  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 251
Expense Example, with Redemption, 3 Years 558
Expense Example, with Redemption, 5 Years 992
Expense Example, with Redemption, 10 Years 1,960
Institutional Shares  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 49
Expense Example, with Redemption, 3 Years 213
Expense Example, with Redemption, 5 Years 390
Expense Example, with Redemption, 10 Years 905
Class R Shares  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 100
Expense Example, with Redemption, 3 Years 387
Expense Example, with Redemption, 5 Years 695
Expense Example, with Redemption, 10 Years $ 1,571