v3.26.3
Investments - Schedule of Current and Long-Term Fixed Maturity Securities, Available-For-Sale (Details) - USD ($)
$ in Millions
Sep. 30, 2026
Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]    
Cost or Amortized Cost $ 28,078 $ 26,889
Gross Unrealized Gains 95 631
Gross Unrealized Losses (1,555) (494)
Allowance For Credit Losses (60) (21)
Estimated Fair Value 26,558 27,005
United States Government securities    
Debt Securities, Available-for-sale [Line Items]    
Cost or Amortized Cost 1,633 1,512
Gross Unrealized Gains 0 10
Gross Unrealized Losses (102) (19)
Allowance For Credit Losses 0 0
Estimated Fair Value 1,531 1,503
Government sponsored securities    
Debt Securities, Available-for-sale [Line Items]    
Cost or Amortized Cost 34 80
Gross Unrealized Gains 0 2
Gross Unrealized Losses (2) (1)
Allowance For Credit Losses 0 0
Estimated Fair Value 32 81
Foreign government securities    
Debt Securities, Available-for-sale [Line Items]    
Cost or Amortized Cost 15 13
Gross Unrealized Gains 0 0
Gross Unrealized Losses (1) 0
Allowance For Credit Losses 0 0
Estimated Fair Value 14 13
States, municipalities and political subdivisions, tax-exempt    
Debt Securities, Available-for-sale [Line Items]    
Cost or Amortized Cost 3,663 3,701
Gross Unrealized Gains 3 76
Gross Unrealized Losses (237) (74)
Allowance For Credit Losses (2) (2)
Estimated Fair Value 3,427 3,701
Corporate securities    
Debt Securities, Available-for-sale [Line Items]    
Cost or Amortized Cost 14,028 13,498
Gross Unrealized Gains 36 419
Gross Unrealized Losses (654) (130)
Allowance For Credit Losses (7) (4)
Estimated Fair Value 13,403 13,783
Residential mortgage-backed securities    
Debt Securities, Available-for-sale [Line Items]    
Cost or Amortized Cost 4,049 3,203
Gross Unrealized Gains 3 43
Gross Unrealized Losses (332) (136)
Allowance For Credit Losses (2) (3)
Estimated Fair Value 3,718 3,107
Commercial mortgage-backed securities    
Debt Securities, Available-for-sale [Line Items]    
Cost or Amortized Cost 1,577 2,078
Gross Unrealized Gains 2 28
Gross Unrealized Losses (68) (31)
Allowance For Credit Losses (2) (2)
Estimated Fair Value 1,509 2,073
Other asset-backed securities    
Debt Securities, Available-for-sale [Line Items]    
Cost or Amortized Cost 3,079 2,804
Gross Unrealized Gains 51 53
Gross Unrealized Losses (159) (103)
Allowance For Credit Losses (47) (10)
Estimated Fair Value $ 2,924 $ 2,744