v3.26.3
Deferred acquisition costs (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Deferred Policy Acquisition Cost [Line Items]        
Balance – beginning of period     $ 10,008  
Amortization expense $ (2,739) $ (2,563) (7,967) $ (7,291)
Balance – end of Period 11,422 9,809 11,422 9,809
Segment Life [Member]        
Deferred Policy Acquisition Cost [Line Items]        
Amortization expense (368) (359) (1,082) (988)
Overseas General Insurance [Member]        
Deferred Policy Acquisition Cost [Line Items]        
Amortization expense (1,085) (975) (3,154) (2,725)
Short-Duration Insurance, Other        
Deferred Policy Acquisition Cost [Line Items]        
Balance – end of Period 4,464 4,197 4,464 4,197
Long-Duration Insurance, Other        
Deferred Policy Acquisition Cost [Line Items]        
Balance – end of Period 6,958 5,612 6,958 5,612
Long-Duration Insurance, Other | Segment Life [Member]        
Deferred Policy Acquisition Cost [Line Items]        
Balance – beginning of period     5,137 4,066
Capitalizations     1,358 1,211
Amortization expense     (487) (407)
Other (including foreign exchange)     163 79
Balance – end of Period 6,171 4,949 6,171 4,949
Long-Duration Insurance, Other | Overseas General Insurance [Member]        
Deferred Policy Acquisition Cost [Line Items]        
Balance – end of Period 787 663 787 663
Term Life Insurance | Segment Life [Member]        
Deferred Policy Acquisition Cost [Line Items]        
Balance – beginning of period     567 469
Capitalizations     187 175
Amortization expense     (123) (111)
Other (including foreign exchange)     3 8
Balance – end of Period 634 541 634 541
Universal Life | Segment Life [Member]        
Deferred Policy Acquisition Cost [Line Items]        
Balance – beginning of period     746 722
Capitalizations     80 90
Amortization expense     (64) (62)
Other (including foreign exchange)     7 5
Balance – end of Period 769 755 769 755
Whole Life Insurance | Segment Life [Member]        
Deferred Policy Acquisition Cost [Line Items]        
Balance – beginning of period     1,296 870
Capitalizations     364 347
Amortization expense     (56) (39)
Other (including foreign exchange)     28 21
Balance – end of Period 1,632 1,199 1,632 1,199
Accident and Health Insurance Product Line [Member] | Segment Life [Member]        
Deferred Policy Acquisition Cost [Line Items]        
Balance – beginning of period     2,136 1,681
Capitalizations     589 521
Amortization expense     (217) (172)
Other (including foreign exchange)     118 33
Balance – end of Period 2,626 2,063 2,626 2,063
Insurance, Other | Segment Life [Member]        
Deferred Policy Acquisition Cost [Line Items]        
Balance – beginning of period     392 324
Capitalizations     138 78
Amortization expense     (27) (23)
Other (including foreign exchange)     7 12
Balance – end of Period $ 510 $ 391 $ 510 $ 391