v3.25.3
First Trust Small Cap Core AlphaDEX Fund Expense Example, No Redemption - First Trust Small Cap Core AlphaDEX Fund - First Trust Small Cap Core AlphaDEX Fund
Jul. 31, 2025
USD ($)
Prospectus [Line Items]  
Expense Example, No Redemption, 1 Year $ 59
Expense Example, No Redemption, 3 Years 186
Expense Example, No Redemption, 5 Years 324
Expense Example, No Redemption, 10 Years $ 726