v3.26.1
Fair Value Measurement - Financial Instruments Carried at Fair Value (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Assets:    
Fixed-maturity securities, available for sale $ 6,817 $ 6,369
Fixed-maturity securities, trading 131 124
Short-term investments, at fair value 792 903
Other invested assets fair value 3 3
Funds withheld, at fair value 296 0
Total assets carried at fair value 8,390 7,912
FG VIEs’ assets, measurement input   167
Other assets 187 174
Liabilities:    
Other liabilities. fair value disclosure 27 21
Total liabilities carried at fair value 174 218
Variable Interest Entity, Primary Beneficiary    
Assets:    
Total assets carried at fair value 164 172
Liabilities:    
Total liabilities carried at fair value 147 197
Obligations of state and political subdivisions    
Assets:    
Fixed-maturity securities, available for sale 1,469 1,769
U.S. government and agencies    
Assets:    
Fixed-maturity securities, available for sale 45 52
Corporate securities    
Assets:    
Fixed-maturity securities, available for sale 3,439 2,952
RMBS    
Assets:    
Fixed-maturity securities, available for sale 726 615
CMBS    
Assets:    
Fixed-maturity securities, available for sale 282 198
Asset-backed securities    
Assets:    
Fixed-maturity securities, available for sale 641 665
Non-U.S. government securities    
Assets:    
Fixed-maturity securities, available for sale 215 118
Level 1    
Assets:    
Fixed-maturity securities, available for sale 0 0
Fixed-maturity securities, trading 0 0
Short-term investments, at fair value 792 898
Other invested assets fair value 0 0
Funds withheld, at fair value 0  
Total assets carried at fair value 881 994
FG VIEs’ assets, measurement input   0
Other assets 89 81
Liabilities:    
Other liabilities. fair value disclosure 0 0
Total liabilities carried at fair value 0 0
Level 1 | Variable Interest Entity, Primary Beneficiary    
Assets:    
Total assets carried at fair value 0 15
Liabilities:    
Total liabilities carried at fair value 0 0
Level 1 | Obligations of state and political subdivisions    
Assets:    
Fixed-maturity securities, available for sale 0 0
Level 1 | U.S. government and agencies    
Assets:    
Fixed-maturity securities, available for sale 0 0
Level 1 | Corporate securities    
Assets:    
Fixed-maturity securities, available for sale 0 0
Level 1 | RMBS    
Assets:    
Fixed-maturity securities, available for sale 0 0
Level 1 | CMBS    
Assets:    
Fixed-maturity securities, available for sale 0 0
Level 1 | Asset-backed securities    
Assets:    
Fixed-maturity securities, available for sale 0 0
Level 1 | Non-U.S. government securities    
Assets:    
Fixed-maturity securities, available for sale 0 0
Level 2    
Assets:    
Fixed-maturity securities, available for sale 6,029 5,536
Fixed-maturity securities, trading 127 120
Short-term investments, at fair value 0 5
Other invested assets fair value 0 0
Funds withheld, at fair value 0  
Total assets carried at fair value 6,248 5,733
FG VIEs’ assets, measurement input   0
Other assets 71 65
Liabilities:    
Other liabilities. fair value disclosure 6 0
Total liabilities carried at fair value 6 0
Level 2 | Variable Interest Entity, Primary Beneficiary    
Assets:    
Total assets carried at fair value 21 7
Liabilities:    
Total liabilities carried at fair value 0 0
Level 2 | Obligations of state and political subdivisions    
Assets:    
Fixed-maturity securities, available for sale 1,459 1,759
Level 2 | U.S. government and agencies    
Assets:    
Fixed-maturity securities, available for sale 45 52
Level 2 | Corporate securities    
Assets:    
Fixed-maturity securities, available for sale 3,279 2,784
Level 2 | RMBS    
Assets:    
Fixed-maturity securities, available for sale 571 471
Level 2 | CMBS    
Assets:    
Fixed-maturity securities, available for sale 282 198
Level 2 | Asset-backed securities    
Assets:    
Fixed-maturity securities, available for sale 178 154
Level 2 | Non-U.S. government securities    
Assets:    
Fixed-maturity securities, available for sale 215 118
Level 3    
Assets:    
Fixed-maturity securities, available for sale 788 833
Fixed-maturity securities, trading 4 4
Short-term investments, at fair value 0 0
Other invested assets fair value 3 3
Funds withheld, at fair value 296  
Total assets carried at fair value 1,261 1,185
FG VIEs’ assets, measurement input   167
Other assets 27 28
Liabilities:    
Other liabilities. fair value disclosure 21 21
Total liabilities carried at fair value 168 218
Level 3 | Variable Interest Entity, Primary Beneficiary    
Assets:    
Total assets carried at fair value 143 150
Liabilities:    
Total liabilities carried at fair value 147 197
Level 3 | Obligations of state and political subdivisions    
Assets:    
Fixed-maturity securities, available for sale 10 10
Level 3 | U.S. government and agencies    
Assets:    
Fixed-maturity securities, available for sale 0 0
Level 3 | Corporate securities    
Assets:    
Fixed-maturity securities, available for sale 160 168
Level 3 | RMBS    
Assets:    
Fixed-maturity securities, available for sale 155 144
Level 3 | CMBS    
Assets:    
Fixed-maturity securities, available for sale 0 0
Level 3 | Asset-backed securities    
Assets:    
Fixed-maturity securities, available for sale 463 511
Level 3 | Non-U.S. government securities    
Assets:    
Fixed-maturity securities, available for sale $ 0 $ 0