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v3.25.1

Investments - Fixed Maturity Securities and Short Term Investments (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024 | Mar. 31, 2024 | Dec. 31, 2023
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Schedule of Investments [Line Items] |  |  |  |
Percent of Total | 100.00% | 100.00% |  |
Amortized Cost | $ 6,774 | $ 6,827 |  |
Allowance for Credit Losses | (45) | (60) | $ (67) | $ (77)
Gross Unrealized Gains | 57 | 44 |  |
Gross Unrealized Losses | (371) | (442) |  |
Estimated Fair Value | $ 6,415 | $ 6,369 |  |
Government agency obligations as a percentage of total mortgage backed securities | 68.00% | 68.00% |  |
Obligations of state and political subdivisions |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Percent of Total | 29.00% | 30.00% |  |
Amortized Cost | $ 2,003 | $ 2,032 |  |
Allowance for Credit Losses | (14) | (14) |  |
Gross Unrealized Gains | 27 | 25 |  |
Gross Unrealized Losses | (92) | (103) |  |
Estimated Fair Value | $ 1,924 | $ 1,940 |  |
U.S. government and agencies |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Percent of Total | 1.00% | 1.00% |  |
Amortized Cost | $ 76 | $ 72 |  |
Allowance for Credit Losses | 0 | 0 |  |
Gross Unrealized Gains | 1 | 1 |  |
Gross Unrealized Losses | (5) | (6) |  |
Estimated Fair Value | $ 72 | $ 67 |  |
Corporate securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Percent of Total | 39.00% | 38.00% |  |
Amortized Cost | $ 2,630 | $ 2,586 |  |
Allowance for Credit Losses | (7) | (7) |  |
Gross Unrealized Gains | 17 | 9 |  |
Gross Unrealized Losses | (163) | (206) |  |
Estimated Fair Value | $ 2,477 | $ 2,382 |  |
RMBS |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Percent of Total | 10.00% | 9.00% |  |
Amortized Cost | $ 649 | $ 657 |  |
Allowance for Credit Losses | (22) | (21) |  |
Gross Unrealized Gains | 5 | 2 |  |
Gross Unrealized Losses | (63) | (71) |  |
Estimated Fair Value | $ 569 | $ 567 |  |
CMBS |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Percent of Total | 3.00% | 3.00% |  |
Amortized Cost | $ 183 | $ 189 |  |
Allowance for Credit Losses | 0 | 0 |  |
Gross Unrealized Gains | 1 | 0 |  |
Gross Unrealized Losses | (2) | (3) |  |
Estimated Fair Value | $ 182 | $ 186 |  |
CLOs |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Percent of Total | 8.00% | 9.00% |  |
Amortized Cost | $ 571 | $ 615 |  |
Allowance for Credit Losses | (1) | (1) |  |
Gross Unrealized Gains | 3 | 6 |  |
Gross Unrealized Losses | (31) | (9) |  |
Estimated Fair Value | $ 542 | $ 611 |  |
Others |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Percent of Total | 9.00% | 9.00% |  |
Amortized Cost | $ 581 | $ 593 |  |
Allowance for Credit Losses | (1) | (17) |  |
Gross Unrealized Gains | 2 | 1 |  |
Gross Unrealized Losses | (4) | (30) |  |
Estimated Fair Value | 578 | 547 |  |
Others | Affiliated Entity |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Amortized Cost | 41 | 41 |  |
Estimated Fair Value | $ 42 | $ 42 |  |
Non-U.S. government securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Percent of Total | 1.00% | 1.00% |  |
Amortized Cost | $ 81 | $ 83 |  |
Allowance for Credit Losses | 0 | 0 |  |
Gross Unrealized Gains | 1 | 0 |  |
Gross Unrealized Losses | (11) | (14) |  |
Estimated Fair Value | $ 71 | $ 69 |  |

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