Alger Focus Equity Fund Average Annual Total Returns - Class I Shares [Member] |
12 Months Ended | 60 Months Ended | 120 Months Ended | |
|---|---|---|---|---|
Oct. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
|
| Russell 1000 Growth Index (reflects no deductions for fees, expenses or taxes)[Member] | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 18.56% | 15.32% | 18.13% | |
| S&P 500 Index (reflects no deductions for fees, expenses or taxes)[Member] | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 17.88% | 14.42% | 14.82% | |
| Class I | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 39.96% | 18.62% | 20.17% | |
| Performance Inception Date | Nov. 08, 1993 | |||
| Class I | After Taxes on Distributions | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 36.47% | 17.23% | 18.92% | |
| Class I | After Taxes on Distributions and Sales | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 24.36% | 14.60% | 16.82% |