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Investments and Cash - Fixed Maturity Securities (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | --- | ---
Investments |  |  |  |
Percent of Total | 100.00% | 100.00% |  |
Amortized Cost | $ 6,827 | $ 6,746 |  |
Allowance for Credit Losses | (60) | (77) | $ (65) | $ (42)
Gross Unrealized Gains | 44 | 55 |  |
Gross Unrealized Losses | (442) | (417) |  |
Fixed-maturity securities, available-for-sale | $ 6,369 | $ 6,307 |  |
Mortgage backed securities consisting of government-agency obligations, percent | 68.00% | 42.00% |  |
Obligations of state and political subdivisions |  |  |  |
Investments |  |  |  |
Percent of Total | 30.00% | 41.00% |  |
Amortized Cost | $ 2,032 | $ 2,733 |  |
Allowance for Credit Losses | (14) | (13) |  |
Gross Unrealized Gains | 25 | 33 |  |
Gross Unrealized Losses | (103) | (92) |  |
Fixed-maturity securities, available-for-sale | $ 1,940 | $ 2,661 |  |
U.S. government and agencies |  |  |  |
Investments |  |  |  |
Percent of Total | 1.00% | 1.00% |  |
Amortized Cost | $ 72 | $ 65 |  |
Allowance for Credit Losses | 0 | 0 |  |
Gross Unrealized Gains | 1 | 1 |  |
Gross Unrealized Losses | (6) | (6) |  |
Fixed-maturity securities, available-for-sale | $ 67 | $ 60 |  |
Corporate securities |  |  |  |
Investments |  |  |  |
Percent of Total | 38.00% | 34.00% |  |
Amortized Cost | $ 2,586 | $ 2,327 |  |
Allowance for Credit Losses | (7) | (6) |  |
Gross Unrealized Gains | 9 | 17 |  |
Gross Unrealized Losses | (206) | (197) |  |
Fixed-maturity securities, available-for-sale | $ 2,382 | $ 2,141 |  |
RMBS |  |  |  |
Investments |  |  |  |
Percent of Total | 9.00% | 6.00% |  |
Amortized Cost | $ 657 | $ 428 |  |
Allowance for Credit Losses | (21) | (21) |  |
Gross Unrealized Gains | 2 | 3 |  |
Gross Unrealized Losses | (71) | (68) |  |
Fixed-maturity securities, available-for-sale | $ 567 | $ 342 |  |
CMBS |  |  |  |
Investments |  |  |  |
Percent of Total | 3.00% | 2.00% |  |
Amortized Cost | $ 189 | $ 157 |  |
Allowance for Credit Losses | 0 | 0 |  |
Gross Unrealized Gains | 0 | 0 |  |
Gross Unrealized Losses | (3) | (6) |  |
Fixed-maturity securities, available-for-sale | $ 186 | $ 151 |  |
CLOs |  |  |  |
Investments |  |  |  |
Percent of Total | 9.00% | 7.00% |  |
Amortized Cost | $ 615 | $ 456 |  |
Allowance for Credit Losses | (1) | 0 |  |
Gross Unrealized Gains | 6 | 1 |  |
Gross Unrealized Losses | (9) | (7) |  |
Fixed-maturity securities, available-for-sale | $ 611 | $ 450 |  |
Others |  |  |  |
Investments |  |  |  |
Percent of Total | 9.00% | 7.00% |  |
Amortized Cost | $ 593 | $ 465 |  |
Allowance for Credit Losses | (17) | (37) |  |
Gross Unrealized Gains | 1 | 0 |  |
Gross Unrealized Losses | (30) | (26) |  |
Fixed-maturity securities, available-for-sale | 547 | 402 |  |
Others | Affiliated Entity |  |  |  |
Investments |  |  |  |
Amortized Cost | 41 | 21 |  |
Fixed-maturity securities, available-for-sale | $ 42 | $ 21 |  |
Non-U.S. government securities |  |  |  |
Investments |  |  |  |
Percent of Total | 1.00% | 2.00% |  |
Amortized Cost | $ 83 | $ 115 |  |
Allowance for Credit Losses | 0 | 0 |  |
Gross Unrealized Gains | 0 | 0 |  |
Gross Unrealized Losses | (14) | (15) |  |
Fixed-maturity securities, available-for-sale | $ 69 | $ 100 |  |

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