v3.26.3
S000034947 [Member] Expense Example - AB Select US Equity Portfolio
Jun. 30, 2026
USD ($)
Advisor Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year $ 121
Expense Example, with Redemption, 3 Years 380
Expense Example, with Redemption, 5 Years 659
Expense Example, with Redemption, 10 Years 1,454
Class A  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 565
Expense Example, with Redemption, 3 Years 863
Expense Example, with Redemption, 5 Years 1,183
Expense Example, with Redemption, 10 Years 2,086
Class C  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 322 [1]
Expense Example, with Redemption, 3 Years 687
Expense Example, with Redemption, 5 Years 1,179
Expense Example, with Redemption, 10 Years 2,344
Class I  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 119
Expense Example, with Redemption, 3 Years 374
Expense Example, with Redemption, 5 Years 648
Expense Example, with Redemption, 10 Years $ 1,431
[1]
If you did not redeem your shares at the end of the period, your expenses would be decreased by approximately $100.