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Investments - Scheduled maturities of available for sale fixed maturities (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023
Fair Value, Fiscal Year Maturity [Abstract] |  |
Available for sale (AFS) fixed maturities | $ 10,398 | $ 10,377
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Collateralized loan obligations and other asset-backed securities average life | 3 years |
Average life of MBS | 6 years |
Fixed maturities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
One year or less | $ 552 |
After one year through five years | 2,738 |
After five years through ten years | 1,296 |
After ten years | 250 |
Fixed maturities amortized cost, Subtotal | 4,836 |
Amortized cost | 10,653 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
One year or less | 540 |
After one year through five years | 2,704 |
After five years through ten years | 1,286 |
After ten years | 235 |
Fixed maturities fair value, Subtotal | 4,765 |
Available for sale (AFS) fixed maturities | $ 10,398 | $ 10,377
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
One year or less | 5.00% |
After one year through five years | 26.00% |
After five years through ten years | 12.00% |
After ten years | 2.00% |
Fixed maturities fair value, Subtotal, Percent | 45.00% |
Fair value, Total, Percent | 100.00% |
Collateralized loan obligations and other asset backed securities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without a single maturity date | $ 3,645 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without a single maturity date | $ 3,593 |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without a single maturity date, percent of fair value | 35.00% |
Mortgage-backed securities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without a single maturity date | $ 2,172 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without a single maturity date | $ 2,040 |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without a single maturity date, percent of fair value | 20.00% |

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