v3.26.1
Shareholders' Equity - Components of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Balance at beginning of period $ 19,591 $ 18,034 $ 19,641 $ 17,937
Other comprehensive income (loss) before reclassifications, after tax 127 163 (137) 353
Reclassification of losses from accumulated other comprehensive loss, after tax 7 37 20 47
Other comprehensive income (loss) 134 200 (117) 400
Amounts attributable to noncontrolling interests (11) (17) 9 (34)
Other       (1)
Balance at end of period 20,032 18,389 20,032 18,389
Net Unrealized Gains (Losses) on Investments with an Allowance for Credit Losses        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Other comprehensive income (loss) before reclassifications, after tax (3) (5) (15) (10)
Reclassification of losses from accumulated other comprehensive loss, after tax 2 6 7 8
Other comprehensive income (loss) (1) 1 (8) (2)
Amounts attributable to noncontrolling interests (1) (1)
Other      
Other comprehensive income (loss) before reclassifications, tax 1 2 4 3
Reclassification of losses from accumulated other comprehensive loss, tax (1) (2) (2) (2)
Net Unrealized Gains (Losses) on Other Investments        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Other comprehensive income (loss) before reclassifications, after tax 186 44 (245) 320
Reclassification of losses from accumulated other comprehensive loss, after tax 4 30 10 36
Other comprehensive income (loss) 190 74 (235) 356
Amounts attributable to noncontrolling interests (15) (6) 19 (30)
Other       (1)
Other comprehensive income (loss) before reclassifications, tax (50) (12) 67 (85)
Reclassification of losses from accumulated other comprehensive loss, tax (1) (10) (3) (11)
Cumulative impact of changes in discount rates used to measure long duration contracts        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Other comprehensive income (loss) before reclassifications, after tax (34) (3) 180 (117)
Reclassification of losses from accumulated other comprehensive loss, after tax
Other comprehensive income (loss) (34) (3) 180 (117)
Amounts attributable to noncontrolling interests 2 1 (15) 10
Other      
Other comprehensive income (loss) before reclassifications, tax 9 0 (48) 31
Reclassification of losses from accumulated other comprehensive loss, tax 0 0 0 0
Unrealized Gains (Losses) on Cash Flow Hedges        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Other comprehensive income (loss) before reclassifications, after tax 2 (3) 3 (6)
Reclassification of losses from accumulated other comprehensive loss, after tax
Other comprehensive income (loss) 2 (3) 3 (6)
Amounts attributable to noncontrolling interests
Other      
Other comprehensive income (loss) before reclassifications, tax (2) 1 (2) 3
Reclassification of losses from accumulated other comprehensive loss, tax 0 0 0 0
Pension and Postretirement Benefits        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Other comprehensive income (loss) before reclassifications, after tax (2) (3) (1)
Reclassification of losses from accumulated other comprehensive loss, after tax 1 1 3 3
Other comprehensive income (loss) (1) 1 0 2
Amounts attributable to noncontrolling interests
Other      
Other comprehensive income (loss) before reclassifications, tax 1 0 1 0
Reclassification of losses from accumulated other comprehensive loss, tax (1) (1) (1) (1)
Foreign Currency Translation        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Other comprehensive income (loss) before reclassifications, after tax (22) 130 (57) 167
Reclassification of losses from accumulated other comprehensive loss, after tax
Other comprehensive income (loss) (22) 130 (57) 167
Amounts attributable to noncontrolling interests 3 (11) 5 (14)
Other      
Other comprehensive income (loss) before reclassifications, tax 0 0 0 0
Reclassification of losses from accumulated other comprehensive loss, tax 0 0 0 0
Accumulated Other Comprehensive Income (Loss)        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Balance at beginning of period (1,298) (1,685) (1,067) (1,867)
Other comprehensive income (loss) 123 183 (108) 366
Balance at end of period (1,175) (1,502) (1,175) (1,502)
Net Unrealized Gains (Losses) on Investments with an Allowance for Credit Losses        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Balance at beginning of period (21) (15) (15) (13)
Balance at end of period (23) (15) (23) (15)
Net Unrealized Gains (Losses) on Other Investments        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Balance at beginning of period (1,298) (1,463) (907) (1,720)
Balance at end of period (1,123) (1,395) (1,123) (1,395)
Cumulative impact of changes in discount rates used to measure long duration contracts        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Balance at beginning of period 373 219 176 324
Balance at end of period 341 217 341 217
Unrealized Gains (Losses) on Cash Flow Hedges        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Balance at beginning of period 3 6 2 9
Balance at end of period 5 3 5 3
Pension and Postretirement Benefits        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Balance at beginning of period (211) (223) (212) (224)
Balance at end of period (212) (222) (212) (222)
Foreign Currency Translation        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Balance at beginning of period (144) (209) (111) (243)
Balance at end of period $ (163) $ (90) $ (163) $ (90)