v3.25.4
OTHER COMPREHENSIVE INCOME (LOSS) - Schedule of Amount Reclassified from Accumulated Other Comprehensive Income (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Net realized capital gains (losses) $ (143) $ 19 $ (276)
Income tax expense (benefit) (296) (120) 363
Other underwriting expenses (1,029) (938) (846)
Net income (loss) 1,591 1,373 $ 2,517
URA(D) of securities | Reclassification from Accumulated Other Comprehensive Income      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Net realized capital gains (losses) 142 (18)  
Income tax expense (benefit) (28) 6  
Net income (loss) 114 (12)  
Benefit plan net gain (loss) | Reclassification from Accumulated Other Comprehensive Income      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Income tax expense (benefit) 0 0  
Other underwriting expenses (2) (2)  
Net income (loss) $ (1) $ (1)