S000003880 [Member] Average Annual Total Returns |
12 Months Ended | 60 Months Ended | 120 Months Ended |
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
|
| Russell 3000 Index (no deduction for fees, expenses or taxes) | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 17.15% | 13.15% | 14.29% |
| Class IA Shares | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 17.11% | 16.25% | 15.49% |
| Class IB Shares | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 16.81% | 15.96% | 15.20% |