Alger Small Cap Growth Portfolio Average Annual Total Returns - Class I2 [Member] |
12 Months Ended | 60 Months Ended | 120 Months Ended | |
|---|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
|
| 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% | |
| Russell 2000 Growth Index (reflects no deductions for fees, expenses or taxes)[Member] | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 13.01% | 3.18% | 9.57% | |
| Class I-2 | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 5.91% | (4.93%) | 8.83% | |
| Performance Inception Date | Sep. 21, 1988 |