v3.25.4
Alger Focus Equity Fund Expense Example, No Redemption - Class A C Shares [Member] - Alger Focus Equity Fund - Class C
Oct. 31, 2025
USD ($)
Prospectus [Line Items]  
Expense Example, No Redemption, 1 Year $ 177
Expense Example, No Redemption, 3 Years 548
Expense Example, No Redemption, 5 Years 944
Expense Example, No Redemption, 10 Years $ 2,052