v3.26.1
Investments (Fair Value and Losses by Investment Category and Length of Time in a Loss Position) (Details) - USD ($)
$ in Millions
Mar. 31, 2026
Dec. 31, 2025
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months $ 41,925 $ 18,962
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 1,142 659
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 32,219 32,102
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 7,324 6,290
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 74,144 51,064
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 8,466 6,949
Investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 40,548 18,291
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 1,109 633
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 31,790 31,831
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 7,248 6,256
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 72,338 50,122
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 8,357 6,889
Non-investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 1,377 671
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 33 26
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 429 271
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 76 34
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 1,806 942
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 109 60
Corporate Debt Securities [Member] | Investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 26,865 10,591
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 691 255
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 21,780 22,666
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 4,168 3,635
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 48,645 33,257
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 4,859 3,890
Corporate Debt Securities [Member] | Non-investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 1,170 652
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 29 25
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 401 258
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 72 31
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 1,571 910
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 101 56
Canadian and Canadian provincial governments | Investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 1,488 1,096
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 37 34
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 650 426
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 96 72
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 2,138 1,522
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 133 106
Residential mortgage-backed securities | Investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 358 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 2 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 534 562
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 72 72
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 892 562
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 74 72
Asset-backed Securities [Member] | Investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 2,962 2,324
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 28 15
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 1,373 1,149
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 143 141
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 4,335 3,473
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 171 156
Asset-backed Securities [Member] | Non-investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 207 19
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 4 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 19 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 1 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 226 19
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 5 1
Commercial mortgage-backed securities | Investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 680 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 7 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 654 705
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 48 50
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 1,334 705
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 55 50
US Government Agencies Debt Securities [Member] | Investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 935 406
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 3 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 486 542
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 254 247
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 1,421 948
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 257 248
US States and Political Subdivisions Debt Securities [Member] | Investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 168 73
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 3 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 391 451
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 81 78
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 559 524
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 84 79
Debt Security, Government, Non-US [Member] | Investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 2,463 1,382
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 89 26
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 1,712 1,901
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 396 350
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 4,175 3,283
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 485 376
Debt Security, Government, Non-US [Member] | Non-investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 0 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 0 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 9 13
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 3 3
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 9 13
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 3 3
JAPAN | Investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 3,586 1,274
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 71 209
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 4,136 3,351
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 1,985 1,607
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 7,722 4,625
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 2,056 1,816
KOREA, REPUBLIC OF | Investment grade securities    
Estimated Fair Values And Gross Unrealized Losses, OTTI Impairment Losses Reported In AOCI [Line Items]    
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 1,043 1,145
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 178 92
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 74 78
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 5 4
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 1,117 1,223
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss $ 183 $ 96