Other Expenses Interest Expense [Member] Annual Total Returns |
12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
Dec. 31, 2022 |
Dec. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Tax-Aware Overlay A Portfolio | Class 1 | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 19.21% | 13.36% | 10.19% | (24.50%) | 18.62% | 6.25% | 16.08% | (10.52%) | 18.83% | 1.33% |