v3.26.1
Investments - Schedule of Available-For-Sale Securities in an Unrealized Loss Position (Details) - USD ($)
$ in Millions
 6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Fair value:    
Less than 12 months $ 88,076 $ 8,238
12 months or longer 15,686 14,135
Total 103,762 22,373
Gross unrealized losses:    
Less than 12 months (668) (14)
12 months or longer (511) (484)
Total (1,179) (498)
Debt Securities, Available-for-Sale, Unrealized Gain (Loss) [Abstract]    
Gross unrealized gain included in accumulated other comprehensive gain/(loss) 179 626
U.S. government obligations    
Fair value:    
Less than 12 months 80,505 6,733
12 months or longer 12,632 10,464
Total 93,137 17,197
Gross unrealized losses:    
Less than 12 months (612) (12)
12 months or longer (282) (226)
Total (894) (238)
U.S. agency obligations    
Fair value:    
Less than 12 months 2,492 706
12 months or longer 0 0
Total 2,492 706
Gross unrealized losses:    
Less than 12 months (30) (1)
12 months or longer 0 0
Total (30) (1)
Non-U.S. government obligations    
Fair value:    
Less than 12 months 5,079 799
12 months or longer 3,054 3,671
Total 8,133 4,470
Gross unrealized losses:    
Less than 12 months (26) (1)
12 months or longer (229) (258)
Total $ (255) $ (259)