v3.25.2
Fair Value Measurement - Financial Instruments Carried at Fair Value (Details) - USD ($)
$ in Millions
Jun. 30, 2025
Dec. 31, 2024
Assets:    
Estimated Fair Value $ 6,498 $ 6,369
Fixed-maturity securities, trading 137 147
Short-term investments, at fair value 939 1,221
Other invested assets 995 926
FG VIEs’ assets 176 147
Other assets 143 131
Liabilities:    
FG VIEs' liabilities 201 164
Other liabilities. fair value disclosure 35 34
Obligations of state and political subdivisions    
Assets:    
Estimated Fair Value 1,772 1,940
U.S. government and agencies    
Assets:    
Estimated Fair Value 38 67
Corporate securities    
Assets:    
Estimated Fair Value 2,746 2,382
RMBS    
Assets:    
Estimated Fair Value 593 567
CMBS    
Assets:    
Estimated Fair Value 151 186
Non-U.S. government securities    
Assets:    
Estimated Fair Value 85 69
Recurring    
Assets:    
Estimated Fair Value 6,498 6,369
Fixed-maturity securities, trading 137 147
Short-term investments, at fair value 939 1,221
Other invested assets 3 4
Other assets 143 131
Total assets carried at fair value 8,017 8,118
Liabilities:    
Other liabilities. fair value disclosure 35 34
Total liabilities carried at fair value 236 198
Recurring | Financial Guaranty Variable Interest Entities    
Liabilities:    
FG VIEs' liabilities 201 164
Recurring | Financial Guaranty Variable Interest Entities    
Assets:    
FG VIEs’ assets 176 147
Recurring | Obligations of state and political subdivisions    
Assets:    
Estimated Fair Value 1,772 1,940
Recurring | U.S. government and agencies    
Assets:    
Estimated Fair Value 38 67
Recurring | Corporate securities    
Assets:    
Estimated Fair Value 2,746 2,382
Recurring | RMBS    
Assets:    
Estimated Fair Value 593 567
Recurring | CMBS    
Assets:    
Estimated Fair Value 151 186
Recurring | Asset-backed securities    
Assets:    
Estimated Fair Value 1,113 1,158
Recurring | Non-U.S. government securities    
Assets:    
Estimated Fair Value 85 69
Recurring | Assets of CIVs, Equity Securities | Consolidated Investment Vehicles    
Assets:    
FG VIEs’ assets 121 99
Recurring | Level 1    
Assets:    
Estimated Fair Value 0 0
Fixed-maturity securities, trading 0 0
Short-term investments, at fair value 936 1,218
Other invested assets 0 0
Other assets 73 65
Total assets carried at fair value 1,024 1,283
Liabilities:    
Other liabilities. fair value disclosure 0 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 | Financial Guaranty Variable Interest Entities    
Assets:    
FG VIEs’ assets 15 0
Recurring | Level 1 | Obligations of state and political subdivisions    
Assets:    
Estimated Fair Value 0 0
Recurring | Level 1 | U.S. government and agencies    
Assets:    
Estimated Fair Value 0 0
Recurring | Level 1 | Corporate securities    
Assets:    
Estimated Fair Value 0 0
Recurring | Level 1 | RMBS    
Assets:    
Estimated Fair Value 0 0
Recurring | Level 1 | CMBS    
Assets:    
Estimated Fair Value 0 0
Recurring | Level 1 | Asset-backed securities    
Assets:    
Estimated Fair Value 0 0
Recurring | Level 1 | Non-U.S. government securities    
Assets:    
Estimated Fair Value 0 0
Recurring | Level 1 | Assets of CIVs, Equity Securities | Consolidated Investment Vehicles    
Assets:    
FG VIEs’ assets 0 0
Recurring | Level 2    
Assets:    
Estimated Fair Value 5,285 5,183
Fixed-maturity securities, trading 133 142
Short-term investments, at fair value 3 3
Other invested assets 0 0
Other assets 61 59
Total assets carried at fair value 5,490 5,387
Liabilities:    
Other liabilities. fair value disclosure 0 0
Total liabilities carried at fair value 0 0
Recurring | Level 2 | Financial Guaranty Variable Interest Entities    
Liabilities:    
FG VIEs' liabilities 0 0
Recurring | Level 2 | Financial Guaranty Variable Interest Entities    
Assets:    
FG VIEs’ assets 8 0
Recurring | Level 2 | Obligations of state and political subdivisions    
Assets:    
Estimated Fair Value 1,762 1,930
Recurring | Level 2 | U.S. government and agencies    
Assets:    
Estimated Fair Value 38 67
Recurring | Level 2 | Corporate securities    
Assets:    
Estimated Fair Value 2,662 2,382
Recurring | Level 2 | RMBS    
Assets:    
Estimated Fair Value 451 422
Recurring | Level 2 | CMBS    
Assets:    
Estimated Fair Value 151 186
Recurring | Level 2 | Asset-backed securities    
Assets:    
Estimated Fair Value 136 127
Recurring | Level 2 | Non-U.S. government securities    
Assets:    
Estimated Fair Value 85 69
Recurring | Level 2 | Assets of CIVs, Equity Securities | Consolidated Investment Vehicles    
Assets:    
FG VIEs’ assets 0 0
Recurring | Level 3    
Assets:    
Estimated Fair Value 1,213 1,186
Fixed-maturity securities, trading 4 5
Short-term investments, at fair value 0 0
Other invested assets 3 4
Other assets 9 7
Total assets carried at fair value 1,503 1,448
Liabilities:    
Other liabilities. fair value disclosure 35 34
Total liabilities carried at fair value 236 198
Recurring | Level 3 | Financial Guaranty Variable Interest Entities    
Liabilities:    
FG VIEs' liabilities 201 164
Recurring | Level 3 | Financial Guaranty Variable Interest Entities    
Assets:    
FG VIEs’ assets 153 147
Recurring | Level 3 | Obligations of state and political subdivisions    
Assets:    
Estimated Fair Value 10 10
Recurring | Level 3 | U.S. government and agencies    
Assets:    
Estimated Fair Value 0 0
Recurring | Level 3 | Corporate securities    
Assets:    
Estimated Fair Value 84 0
Recurring | Level 3 | RMBS    
Assets:    
Estimated Fair Value 142 145
Recurring | Level 3 | CMBS    
Assets:    
Estimated Fair Value 0 0
Recurring | Level 3 | Asset-backed securities    
Assets:    
Estimated Fair Value 977 1,031
Recurring | Level 3 | Non-U.S. government securities    
Assets:    
Estimated Fair Value 0 0
Recurring | Level 3 | Assets of CIVs, Equity Securities | Consolidated Investment Vehicles    
Assets:    
FG VIEs’ assets $ 121 $ 99