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Investments - Scheduled maturities of available for sale fixed maturities (Details) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024
Fair Value, Fiscal Year Maturity [Abstract] |  |
Available for sale (AFS) fixed maturities | $ 10,518 | $ 10,398
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Average life of ABS | 3 years |
Average life of MBS | 6 years |
Fixed maturities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
One year or less | $ 759 |
After one year through five years | 2,349 |
After five years through ten years | 1,325 |
After ten years | 231 |
Fixed maturities amortized cost, Subtotal | 4,664 |
Amortized cost | 10,572 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
One year or less | 751 |
After one year through five years | 2,369 |
After five years through ten years | 1,364 |
After ten years | 220 |
Fixed maturities fair value, subtotal | 4,704 |
Available for sale (AFS) fixed maturities | $ 10,518 | $ 10,398
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
One year or less | 7.00% |
After one year through five years | 23.00% |
After five years through ten years | 13.00% |
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 single maturity date | $ 3,521 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | $ 3,503 |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | 33.00% |
Mortgage-backed securities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | $ 2,387 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | $ 2,311 |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | 22.00% |

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