Alger International Opportunities 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 |
|
| MSCI ACWI ex USA Gross Index (reflects no deductions for fees, expenses or taxes)[Member] | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 33.11% | 8.46% | 8.95% | |
| Class I | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 18.54% | 2.04% | 6.83% | |
| Performance Inception Date | May 31, 2013 | |||
| Class I | After Taxes on Distributions | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 15.73% | 0.93% | 5.60% | |
| Class I | After Taxes on Distributions and Sales | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 13.15% | 1.56% | 5.10% |