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 B Portfolio | Class 1 | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 8.99% | 6.19% | 7.36% | (12.92%) | 8.26% | 6.59% | 8.61% | (3.60%) | 8.67% | 1.68% |