v3.26.3
Unpaid Claims and Claims Expense Short Duration Contracts (Rollforward Of Claims) (Details) - USD ($)
$ in Millions
 3 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Dec. 31, 2025
Dec. 31, 2024
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]        
Liability for Claims and Claims Adjustment Expense $ 3,067 $ 3,032 $ 3,011 $ 2,693
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments (37) (61) (43) (53)
Liability For Unpaid Claims And Claims Adjustment Expense Net Of Recoverable 3,030 2,971 $ 2,968 $ 2,640
Current Year Claims and Claims Adjustment Expense 1,232 1,521    
Prior Year Claims and Claims Adjustment Expense (22) (55)    
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims 1,210 1,576    
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Current Year (287) (356)    
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Prior Years (882) (991)    
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid (1,169) (1,347)    
Interest On Liability For Policy And Contract Claims 33 26    
Liability for Unpaid Claims and Claims Adjustment Expense, Foreign Currency Translation Gain (Loss) (12) 76    
Liability for Unpaid Claims and Claims Adjustment Expense Other $ 21 $ 102