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Investments - Scheduled maturities of available for sale fixed maturities (Details) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2023 | Dec. 31, 2022
Fair Value, Fiscal Year Maturity [Abstract] |  |
Available for sale (AFS) fixed maturities | $ 9,885 | $ 10,095
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Average life of ABS | 3 years |
Average life of MBS | 6 years 6 months |
Fixed maturities: |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
One year or less | $ 479 |
After one year through five years | 2,551 |
After five years through ten years | 1,075 |
After ten years | 343 |
Fixed maturities amortized cost, Subtotal | 4,448 |
Amortized Cost | 10,472 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
One year or less | 471 |
After one year through five years | 2,414 |
After five years through ten years | 1,024 |
After ten years | 323 |
Fixed maturities fair value, Subtotal | 4,232 |
Available for sale (AFS) fixed maturities | $ 9,885 | $ 10,095
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
One year or less | 5.00% |
After one year through five years | 24.00% |
After five years through ten years | 10.00% |
After ten years | 3.00% |
Fixed maturities fair value, Subtotal, Percent | 42.00% |
Fair value, Total, Percent | 100.00% |
Collateralized loan obligations and other asset backed securities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | $ 4,235 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | $ 4,028 |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | 41.00% |
Mortgage-backed securities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | $ 1,789 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | $ 1,625 |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | 17.00% |

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