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Investments - Scheduled maturities of available for sale fixed maturities (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2026 | Dec. 31, 2025
Fair Value, Fiscal Year Maturity [Abstract] |  |
Fair Value | $ 11,397 | $ 11,052
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Average life of ABS | 3 years 6 months |
Average life of MBS | 6 years |
Fixed maturities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
One year or less | $ 694 |
After one year through five years | 2,125 |
After five years through ten years | 1,459 |
After ten years | 216 |
Fixed maturities amortized cost, Subtotal | 4,494 |
Amortized cost | 11,523 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
One year or less | 687 |
After one year through five years | 2,123 |
After five years through ten years | 1,472 |
After ten years | 200 |
Fixed maturities fair value, subtotal | 4,482 |
Fair Value | $ 11,397 | $ 11,052
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
One year or less | 6.00% |
After one year through five years | 19.00% |
After five years through ten years | 13.00% |
After ten years | 2.00% |
Fixed maturities fair value, subtotal, percent | 40.00% |
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 | $ 3,784 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | $ 3,755 |
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 | $ 3,245 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | $ 3,160 |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Fixed maturities without single maturity date | 27.00% |

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