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Investments - Scheduled maturities of available for sale fixed maturities (Details) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2024 | Dec. 31, 2023
Fair Value, Fiscal Year Maturity [Abstract] |  |
Available for sale (AFS) fixed maturities | $ 10,196 | $ 10,377
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 | $ 414 |
After one year through five years | 2,857 |
After five years through ten years | 1,226 |
After ten years | 284 |
Fixed maturities amortized cost, Subtotal | 4,781 |
Amortized cost | 10,563 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
One year or less | 404 |
After one year through five years | 2,764 |
After five years through ten years | 1,204 |
After ten years | 269 |
Fixed maturities fair value, subtotal | 4,641 |
Available for sale (AFS) fixed maturities | $ 10,196 | $ 10,377
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
One year or less | 4.00% |
After one year through five years | 27.00% |
After five years through ten years | 12.00% |
After ten years | 3.00% |
Fixed maturities fair value, subtotal, percent | 46.00% |
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 | $ 3,908 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | $ 3,822 |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | 37.00% |
Mortgage-backed securities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | $ 1,874 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | $ 1,733 |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | 17.00% |

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