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Fair Value Measurement - Financial Instruments Carried at Fair Value (Details) - USD ($) $ in Millions | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Assets: |  |
Estimated Fair Value | $ 6,267 | $ 7,119
Fixed-maturity securities, trading | 350 | 303
Short-term investments, at fair value | 1,426 | 810
Other invested assets | 765 | 133
FG VIEs’ assets | 326 | 413
Other assets | 112 | 148
Liabilities: |  |
Credit derivative liabilities | 50 | 163
FG VIEs' liabilities | 542 | 715
Obligations of state and political subdivisions |  |
Assets: |  |
Estimated Fair Value | 2,766 | 3,394
U.S. government and agencies |  |
Assets: |  |
Estimated Fair Value | 58 | 111
Corporate securities |  |
Assets: |  |
Estimated Fair Value | 2,009 | 2,084
RMBS |  |
Assets: |  |
Estimated Fair Value | 330 | 340
CMBS |  |
Assets: |  |
Estimated Fair Value | 188 | 271
Non-U.S. government securities |  |
Assets: |  |
Estimated Fair Value | 93 | 98
Fair Value Measured at Net Asset Value Per Share | Fund investments: | Equity securities and warrants | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 5
Recurring |  |
Assets: |  |
Short-term investments, at fair value | 1,426 | 810
Other invested assets | 3 | 7
Other assets | 112 | 148
Total assets carried at fair value | 8,802 | 14,031
Liabilities: |  |
Credit derivative liabilities | 50 | 163
Other liabilities |  | 7
Total liabilities carried at fair value | 592 | 5,316
Recurring | Financial Guaranty Variable Interest Entities |  |
Liabilities: |  |
FG VIEs' liabilities | 542 | 715
Recurring | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 4,431
Recurring | Financial Guaranty Variable Interest Entities |  |
Assets: |  |
FG VIEs’ assets | 326 | 413
Recurring | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets | 318 | 5,231
Recurring | Warehouse financing debt | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 313
Recurring | Securitized borrowing | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 28
Recurring | CLO obligations of CFEs | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 4,090
Recurring | Fixed-maturity securities, available-for-sale |  |
Assets: |  |
Estimated Fair Value | 6,267 | 7,119
Fixed-maturity securities, trading | 350 | 303
Recurring | Fixed-maturity securities, available-for-sale | Obligations of state and political subdivisions |  |
Assets: |  |
Estimated Fair Value | 2,766 | 3,394
Recurring | Fixed-maturity securities, available-for-sale | U.S. government and agencies |  |
Assets: |  |
Estimated Fair Value | 58 | 111
Recurring | Fixed-maturity securities, available-for-sale | Corporate securities |  |
Assets: |  |
Estimated Fair Value | 2,009 | 2,084
Recurring | Fixed-maturity securities, available-for-sale | RMBS |  |
Assets: |  |
Estimated Fair Value | 330 | 340
Recurring | Fixed-maturity securities, available-for-sale | CMBS |  |
Assets: |  |
Estimated Fair Value | 188 | 271
Recurring | Fixed-maturity securities, available-for-sale | Asset-backed securities |  |
Assets: |  |
Estimated Fair Value | 823 | 821
Recurring | Fixed-maturity securities, available-for-sale | Non-U.S. government securities |  |
Assets: |  |
Estimated Fair Value | 93 | 98
Recurring | Fund investments: | Corporate securities | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 96
Recurring | Fund investments: | Equity securities and warrants | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets | 79 | 302
Recurring | Fund investments: | Structured products | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets | 239 | 128
Recurring | CLOs and CLO warehouse assets: | Corporate securities | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 4,570
Recurring | CLOs and CLO warehouse assets: | Short-term investments | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 135
Recurring | Level 1 |  |
Assets: |  |
Short-term investments, at fair value | 1,418 | 771
Other invested assets | 0 | 2
Other assets | 51 | 54
Total assets carried at fair value | 1,469 | 962
Liabilities: |  |
Credit derivative liabilities | 0 | 0
Other liabilities |  | 0
Total liabilities carried at fair value | 0 | 0
Recurring | Level 1 | Financial Guaranty Variable Interest Entities |  |
Liabilities: |  |
FG VIEs' liabilities | 0 | 0
Recurring | Level 1 | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 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 | 135
Recurring | Level 1 | Warehouse financing debt | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 0
Recurring | Level 1 | Securitized borrowing | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 0
Recurring | Level 1 | CLO obligations of CFEs | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 0
Recurring | Level 1 | Fixed-maturity securities, available-for-sale |  |
Assets: |  |
Estimated Fair Value | 0 | 0
Fixed-maturity securities, trading | 0 | 0
Recurring | Level 1 | Fixed-maturity securities, available-for-sale | Obligations of state and political subdivisions |  |
Assets: |  |
Estimated Fair Value | 0 | 0
Recurring | Level 1 | Fixed-maturity securities, available-for-sale | U.S. government and agencies |  |
Assets: |  |
Estimated Fair Value | 0 | 0
Recurring | Level 1 | Fixed-maturity securities, available-for-sale | Corporate securities |  |
Assets: |  |
Estimated Fair Value | 0 | 0
Recurring | Level 1 | Fixed-maturity securities, available-for-sale | RMBS |  |
Assets: |  |
Estimated Fair Value | 0 | 0
Recurring | Level 1 | Fixed-maturity securities, available-for-sale | CMBS |  |
Assets: |  |
Estimated Fair Value | 0 | 0
Recurring | Level 1 | Fixed-maturity securities, available-for-sale | Asset-backed securities |  |
Assets: |  |
Estimated Fair Value | 0 | 0
Recurring | Level 1 | Fixed-maturity securities, available-for-sale | Non-U.S. government securities |  |
Assets: |  |
Estimated Fair Value | 0 | 0
Recurring | Level 1 | Fund investments: | Corporate securities | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 0
Recurring | Level 1 | Fund investments: | Equity securities and warrants | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets | 0 | 0
Recurring | Level 1 | Fund investments: | Structured products | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets | 0 | 0
Recurring | Level 1 | CLOs and CLO warehouse assets: | Corporate securities | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 0
Recurring | Level 1 | CLOs and CLO warehouse assets: | Short-term investments | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 135
Recurring | Level 2 |  |
Assets: |  |
Short-term investments, at fair value | 8 | 39
Other invested assets | 0 | 0
Other assets | 48 | 46
Total assets carried at fair value | 5,938 | 11,353
Liabilities: |  |
Credit derivative liabilities | 0 | 0
Other liabilities |  | 7
Total liabilities carried at fair value | 0 | 284
Recurring | Level 2 | Financial Guaranty Variable Interest Entities |  |
Liabilities: |  |
FG VIEs' liabilities | 0 | 0
Recurring | Level 2 | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 277
Recurring | Level 2 | Financial Guaranty Variable Interest Entities |  |
Assets: |  |
FG VIEs’ assets | 146 | 209
Recurring | Level 2 | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets | 70 | 4,657
Recurring | Level 2 | Warehouse financing debt | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 277
Recurring | Level 2 | Securitized borrowing | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 0
Recurring | Level 2 | CLO obligations of CFEs | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 0
Recurring | Level 2 | Fixed-maturity securities, available-for-sale |  |
Assets: |  |
Estimated Fair Value | 5,316 | 6,099
Fixed-maturity securities, trading | 350 | 303
Recurring | Level 2 | Fixed-maturity securities, available-for-sale | Obligations of state and political subdivisions |  |
Assets: |  |
Estimated Fair Value | 2,764 | 3,347
Recurring | Level 2 | Fixed-maturity securities, available-for-sale | U.S. government and agencies |  |
Assets: |  |
Estimated Fair Value | 58 | 111
Recurring | Level 2 | Fixed-maturity securities, available-for-sale | Corporate securities |  |
Assets: |  |
Estimated Fair Value | 2,009 | 2,084
Recurring | Level 2 | Fixed-maturity securities, available-for-sale | RMBS |  |
Assets: |  |
Estimated Fair Value | 177 | 161
Recurring | Level 2 | Fixed-maturity securities, available-for-sale | CMBS |  |
Assets: |  |
Estimated Fair Value | 188 | 271
Recurring | Level 2 | Fixed-maturity securities, available-for-sale | Asset-backed securities |  |
Assets: |  |
Estimated Fair Value | 27 | 27
Recurring | Level 2 | Fixed-maturity securities, available-for-sale | Non-U.S. government securities |  |
Assets: |  |
Estimated Fair Value | 93 | 98
Recurring | Level 2 | Fund investments: | Corporate securities | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 0
Recurring | Level 2 | Fund investments: | Equity securities and warrants | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets | 4 | 5
Recurring | Level 2 | Fund investments: | Structured products | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets | 66 | 82
Recurring | Level 2 | CLOs and CLO warehouse assets: | Corporate securities | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 4,570
Recurring | Level 2 | CLOs and CLO warehouse assets: | Short-term investments | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 0
Recurring | Level 3 |  |
Assets: |  |
Short-term investments, at fair value | 0 | 0
Other invested assets | 3 | 5
Other assets | 13 | 48
Total assets carried at fair value | 1,395 | 1,716
Liabilities: |  |
Credit derivative liabilities | 50 | 163
Other liabilities |  | 0
Total liabilities carried at fair value | 592 | 5,032
Recurring | Level 3 | Financial Guaranty Variable Interest Entities |  |
Liabilities: |  |
FG VIEs' liabilities | 542 | 715
Recurring | Level 3 | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 4,154
Recurring | Level 3 | Financial Guaranty Variable Interest Entities |  |
Assets: |  |
FG VIEs’ assets | 180 | 204
Recurring | Level 3 | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets | 248 | 439
Recurring | Level 3 | Warehouse financing debt | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 36
Recurring | Level 3 | Securitized borrowing | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 28
Recurring | Level 3 | CLO obligations of CFEs | Consolidated Investment Vehicles |  |
Liabilities: |  |
FG VIEs' liabilities |  | 4,090
Recurring | Level 3 | Fixed-maturity securities, available-for-sale |  |
Assets: |  |
Estimated Fair Value | 951 | 1,020
Fixed-maturity securities, trading | 0 | 0
Recurring | Level 3 | Fixed-maturity securities, available-for-sale | Obligations of state and political subdivisions |  |
Assets: |  |
Estimated Fair Value | 2 | 47
Recurring | Level 3 | Fixed-maturity securities, available-for-sale | U.S. government and agencies |  |
Assets: |  |
Estimated Fair Value | 0 | 0
Recurring | Level 3 | Fixed-maturity securities, available-for-sale | Corporate securities |  |
Assets: |  |
Estimated Fair Value | 0 | 0
Recurring | Level 3 | Fixed-maturity securities, available-for-sale | RMBS |  |
Assets: |  |
Estimated Fair Value | 153 | 179
Recurring | Level 3 | Fixed-maturity securities, available-for-sale | CMBS |  |
Assets: |  |
Estimated Fair Value | 0 | 0
Recurring | Level 3 | Fixed-maturity securities, available-for-sale | Asset-backed securities |  |
Assets: |  |
Estimated Fair Value | 796 | 794
Recurring | Level 3 | Fixed-maturity securities, available-for-sale | Non-U.S. government securities |  |
Assets: |  |
Estimated Fair Value | 0 | 0
Recurring | Level 3 | Fund investments: | Corporate securities | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 96
Recurring | Level 3 | Fund investments: | Equity securities and warrants | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets | 75 | 297
Recurring | Level 3 | Fund investments: | Structured products | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets | $ 173 | 46
Recurring | Level 3 | CLOs and CLO warehouse assets: | Corporate securities | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | 0
Recurring | Level 3 | CLOs and CLO warehouse assets: | Short-term investments | Consolidated Investment Vehicles |  |
Assets: |  |
FG VIEs’ assets |  | $ 0

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