v3.26.3
Investments - Activity in Allowance for Credit Loss Aggregated by Investment Category (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Debt Securities, Available-for-sale, Allowance for Credit Loss        
Balance at Beginning of Period $ (71) $ (97) $ (104) $ (62)
Additions        
For credit losses on securities for which losses were not previously recorded 0 0 (11) (19)
(Additions) reductions in allowance recorded on previously impaired securities 0 1 13 (16)
Reductions        
For securities sold during the period 0 0 20 1
For securities intended/required to be sold prior to recovery of amortized cost basis 0 0 0 0
Write offs charged against the allowance 0 0 11 0
Recoveries of amounts previously written off 0 0 0 0
Balance at End of Period (71) (96) (71) (96)
Asset-backed securities        
Debt Securities, Available-for-sale, Allowance for Credit Loss        
Balance at Beginning of Period (14) (24) (25) (13)
Additions        
For credit losses on securities for which losses were not previously recorded 0 0 (4) (4)
(Additions) reductions in allowance recorded on previously impaired securities 2 3 4 (5)
Reductions        
For securities sold during the period 0 0 2 1
For securities intended/required to be sold prior to recovery of amortized cost basis 0 0 0 0
Write offs charged against the allowance 0 0 11 0
Recoveries of amounts previously written off 0 0 0 0
Balance at End of Period (12) (21) (12) (21)
Commercial mortgage-backed securities        
Debt Securities, Available-for-sale, Allowance for Credit Loss        
Balance at Beginning of Period (56) (53) (61) (49)
Additions        
For credit losses on securities for which losses were not previously recorded 0 0 (7) (1)
(Additions) reductions in allowance recorded on previously impaired securities (1) (2) 11 (5)
Reductions        
For securities sold during the period 0 0 0 0
For securities intended/required to be sold prior to recovery of amortized cost basis 0 0 0 0
Write offs charged against the allowance 0 0 0 0
Recoveries of amounts previously written off 0 0 0 0
Balance at End of Period (57) (55) (57) (55)
Corporates        
Debt Securities, Available-for-sale, Allowance for Credit Loss        
Balance at Beginning of Period   (20) (17) 0
Additions        
For credit losses on securities for which losses were not previously recorded   0 0 (14)
(Additions) reductions in allowance recorded on previously impaired securities   1 (1) (5)
Reductions        
For securities sold during the period   0 18 0
For securities intended/required to be sold prior to recovery of amortized cost basis   0 0 0
Write offs charged against the allowance   0 0 0
Recoveries of amounts previously written off   0 0 0
Balance at End of Period 0 (19) 0 (19)
Residential mortgage-backed securities        
Debt Securities, Available-for-sale, Allowance for Credit Loss        
Balance at Beginning of Period (1) 0 (1) 0
Additions        
For credit losses on securities for which losses were not previously recorded 0 0 0 0
(Additions) reductions in allowance recorded on previously impaired securities (1) (1) (1) (1)
Reductions        
For securities sold during the period 0 0 0 0
For securities intended/required to be sold prior to recovery of amortized cost basis 0 0 0  
Write offs charged against the allowance 0 0 0 0
Recoveries of amounts previously written off 0 0 0 0
Balance at End of Period $ (2) $ (1) $ (2) $ (1)