v3.25.2
Fair Value (Assets and liabilities measured at fair value on a recurring basis) (Details) - USD ($)
$ in Millions
Jun. 30, 2025
Dec. 31, 2024
Fixed maturity securities:    
Fixed maturity securities $ 42,799 $ 41,111
Equity securities:    
Equity securities 727 659
Short-term and other 1,556 1,922
Total assets 45,082 43,692
Total liabilities 0 0
Corporate and other bonds    
Fixed maturity securities:    
Fixed maturity securities 26,655 25,841
States, municipalities and political subdivisions    
Fixed maturity securities:    
Fixed maturity securities 7,375 6,804
Asset-backed    
Fixed maturity securities:    
Fixed maturity securities 8,769 8,466
Common Stock    
Equity securities:    
Equity securities 223 180
Non-redeemable preferred stock    
Equity securities:    
Equity securities 504 479
Level 1    
Fixed maturity securities:    
Fixed maturity securities 229 223
Equity securities:    
Equity securities 248 198
Short-term and other 1,511 1,852
Total assets 1,988 2,273
Total liabilities 0 0
Level 1 | Corporate and other bonds    
Fixed maturity securities:    
Fixed maturity securities 229 223
Level 1 | States, municipalities and political subdivisions    
Fixed maturity securities:    
Fixed maturity securities 0 0
Level 1 | Asset-backed    
Fixed maturity securities:    
Fixed maturity securities 0 0
Level 1 | Common Stock    
Equity securities:    
Equity securities 213 162
Level 1 | Non-redeemable preferred stock    
Equity securities:    
Equity securities 35 36
Level 2    
Fixed maturity securities:    
Fixed maturity securities 40,252 38,692
Equity securities:    
Equity securities 469 441
Short-term and other 45 70
Total assets 40,766 39,203
Total liabilities 0 0
Level 2 | Corporate and other bonds    
Fixed maturity securities:    
Fixed maturity securities 25,038 24,340
Level 2 | States, municipalities and political subdivisions    
Fixed maturity securities:    
Fixed maturity securities 7,331 6,762
Level 2 | Asset-backed    
Fixed maturity securities:    
Fixed maturity securities 7,883 7,590
Level 2 | Common Stock    
Equity securities:    
Equity securities 0 0
Level 2 | Non-redeemable preferred stock    
Equity securities:    
Equity securities 469 441
Level 3    
Fixed maturity securities:    
Fixed maturity securities 2,318 2,196
Equity securities:    
Equity securities 10 20
Short-term and other 0 0
Total assets 2,328 2,216
Total liabilities 0 0
Level 3 | Corporate and other bonds    
Fixed maturity securities:    
Fixed maturity securities 1,388 1,278
Level 3 | States, municipalities and political subdivisions    
Fixed maturity securities:    
Fixed maturity securities 44 42
Level 3 | Asset-backed    
Fixed maturity securities:    
Fixed maturity securities 886 876
Level 3 | Common Stock    
Equity securities:    
Equity securities 10 18
Level 3 | Non-redeemable preferred stock    
Equity securities:    
Equity securities $ 0 $ 2