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Fair Value Measurement - Financial Instruments Carried at Fair Value (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Assets: |  |
Fixed-maturity securities, available-for-sale | $ 6,369 | $ 6,307
Fixed-maturity securities, trading, at fair value | 147 | 318
Short-term investments, at fair value | 1,221 | 1,661
Other invested assets | 926 | 829
FG VIEs’ assets | 147 | 174
Other assets | 131 | 123
Liabilities: |  |
Liabilities of CIVs | 164 | 554
Obligations of state and political subdivisions |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 1,940 | 2,661
U.S. government and agencies |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 67 | 60
Corporate securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 2,382 | 2,141
RMBS |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 567 | 342
CMBS |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 186 | 151
Non-U.S. government securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 69 | 100
Recurring |  |
Assets: |  |
Other invested assets | 4 | 3
Other assets | 131 | 123
Total assets carried at fair value | 8,118 | 8,917
Liabilities: |  |
Other liabilities | 34 | 53
Total liabilities carried at fair value | 198 | 607
Recurring | Financial Guaranty Variable Interest Entities |  |
Liabilities: |  |
Liabilities of CIVs | 164 | 554
Recurring | Financial Guaranty Variable Interest Entities |  |
Assets: |  |
FG VIEs’ assets | 147 | 174
Recurring | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 331
Recurring | Level 1 |  |
Assets: |  |
Other invested assets | 0 | 0
Other assets | 65 | 55
Total assets carried at fair value | 1,283 | 1,712
Liabilities: |  |
Other liabilities | 0 | 0
Total liabilities carried at fair value | 0 | 0
Recurring | Level 1 | Financial Guaranty Variable Interest Entities |  |
Liabilities: |  |
Liabilities of CIVs | 0 | 0
Recurring | Level 1 | Financial Guaranty Variable Interest Entities |  |
Assets: |  |
FG VIEs’ assets | 0 | 0
Recurring | Level 1 | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 0
Recurring | Level 2 |  |
Assets: |  |
Other invested assets | 0 | 0
Other assets | 59 | 52
Total assets carried at fair value | 5,387 | 5,780
Liabilities: |  |
Other liabilities | 0 | 0
Total liabilities carried at fair value | 0 | 0
Recurring | Level 2 | Financial Guaranty Variable Interest Entities |  |
Liabilities: |  |
Liabilities of CIVs | 0 | 0
Recurring | Level 2 | Financial Guaranty Variable Interest Entities |  |
Assets: |  |
FG VIEs’ assets | 0 | 0
Recurring | Level 2 | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 62
Recurring | Level 3 |  |
Assets: |  |
Other invested assets | 4 | 3
Other assets | 7 | 16
Total assets carried at fair value | 1,448 | 1,425
Liabilities: |  |
Other liabilities | 34 | 53
Total liabilities carried at fair value | 198 | 607
Recurring | Level 3 | Financial Guaranty Variable Interest Entities |  |
Liabilities: |  |
Liabilities of CIVs | 164 | 554
Recurring | Level 3 | Financial Guaranty Variable Interest Entities |  |
Assets: |  |
FG VIEs’ assets | 147 | 174
Recurring | Level 3 | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 269
Fixed-maturity securities | Recurring |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 6,369 | 6,307
Fixed-maturity securities, trading, at fair value | 147 | 318
Fixed-maturity securities | Recurring | Obligations of state and political subdivisions |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 1,940 | 2,661
Fixed-maturity securities | Recurring | U.S. government and agencies |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 67 | 60
Fixed-maturity securities | Recurring | Corporate securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 2,382 | 2,141
Fixed-maturity securities | Recurring | RMBS |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 567 | 342
Fixed-maturity securities | Recurring | CMBS |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 186 | 151
Fixed-maturity securities | Recurring | Asset-backed securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 1,158 | 852
Fixed-maturity securities | Recurring | Non-U.S. government securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 69 | 100
Fixed-maturity securities | Recurring | Level 1 |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 0 | 0
Fixed-maturity securities, trading, at fair value | 0 | 0
Fixed-maturity securities | Recurring | Level 1 | Obligations of state and political subdivisions |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 0 | 0
Fixed-maturity securities | Recurring | Level 1 | U.S. government and agencies |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 0 | 0
Fixed-maturity securities | Recurring | Level 1 | Corporate securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 0 | 0
Fixed-maturity securities | Recurring | Level 1 | RMBS |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 0 | 0
Fixed-maturity securities | Recurring | Level 1 | CMBS |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 0 | 0
Fixed-maturity securities | Recurring | Level 1 | Asset-backed securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 0 | 0
Fixed-maturity securities | Recurring | Level 1 | Non-U.S. government securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 0 | 0
Fixed-maturity securities | Recurring | Level 2 |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 5,183 | 5,344
Fixed-maturity securities, trading, at fair value | 142 | 318
Fixed-maturity securities | Recurring | Level 2 | Obligations of state and political subdivisions |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 1,930 | 2,655
Fixed-maturity securities | Recurring | Level 2 | U.S. government and agencies |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 67 | 60
Fixed-maturity securities | Recurring | Level 2 | Corporate securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 2,382 | 2,141
Fixed-maturity securities | Recurring | Level 2 | RMBS |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 422 | 188
Fixed-maturity securities | Recurring | Level 2 | CMBS |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 186 | 151
Fixed-maturity securities | Recurring | Level 2 | Asset-backed securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 127 | 49
Fixed-maturity securities | Recurring | Level 2 | Non-U.S. government securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 69 | 100
Fixed-maturity securities | Recurring | Level 3 |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 1,186 | 963
Fixed-maturity securities, trading, at fair value | 5 | 0
Fixed-maturity securities | Recurring | Level 3 | Obligations of state and political subdivisions |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 10 | 6
Fixed-maturity securities | Recurring | Level 3 | U.S. government and agencies |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 0 | 0
Fixed-maturity securities | Recurring | Level 3 | Corporate securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 0 | 0
Fixed-maturity securities | Recurring | Level 3 | RMBS |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 145 | 154
Fixed-maturity securities | Recurring | Level 3 | CMBS |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 0 | 0
Fixed-maturity securities | Recurring | Level 3 | Asset-backed securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 1,031 | 803
Fixed-maturity securities | Recurring | Level 3 | Non-U.S. government securities |  |
Assets: |  |
Fixed-maturity securities, available-for-sale | 0 | 0
Short-term investments | Recurring |  |
Assets: |  |
Fixed-maturity securities, available-for-sale |  | 1,661
Short-term investments, at fair value | 1,221 |
Short-term investments | Recurring | Level 1 |  |
Assets: |  |
Fixed-maturity securities, available-for-sale |  | 1,657
Short-term investments, at fair value | 1,218 |
Short-term investments | Recurring | Level 2 |  |
Assets: |  |
Fixed-maturity securities, available-for-sale |  | 4
Short-term investments, at fair value | 3 |
Short-term investments | Recurring | Level 3 |  |
Assets: |  |
Fixed-maturity securities, available-for-sale |  | 0
Short-term investments, at fair value | 0 |
Fund Investments | Recurring | Assets of CIVs, equity securities | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets | 99 |
Fund Investments | Recurring | Equity Securities | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 83
Fund Investments | Recurring | Structured products | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 248
Fund Investments | Recurring | Level 1 | Assets of CIVs, equity securities | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets | 0 |
Fund Investments | Recurring | Level 1 | Equity Securities | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 0
Fund Investments | Recurring | Level 1 | Structured products | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 0
Fund Investments | Recurring | Level 2 | Assets of CIVs, equity securities | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets | 0 |
Fund Investments | Recurring | Level 2 | Equity Securities | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 3
Fund Investments | Recurring | Level 2 | Structured products | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 59
Fund Investments | Recurring | Level 3 | Assets of CIVs, equity securities | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets | $ 99 |
Fund Investments | Recurring | Level 3 | Equity Securities | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 80
Fund Investments | Recurring | Level 3 | Structured products | Consolidated investment vehicles |  |
Assets: |  |
FG VIEs’ assets |  | $ 189

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