v3.26.1
Financial Instruments - Gross Unrealized Losses and Fair Values for Investments in Unrealized Loss Position (Details) - USD ($)
$ in Millions
Mar. 31, 2026
Dec. 31, 2025
Investments, Unrealized Loss Position [Line Items]    
Less than 12 Months, Fair Value $ 25,083 $ 6,522
Less than 12 Months, Unrealized Loss (142) (13)
12 Months or Greater, Fair Value 4,688 6,638
12 Months or Greater, Unrealized Loss (155) (165)
Total Fair Value 29,771 13,160
Total Unrealized Loss (297) (178)
Government bonds    
Investments, Unrealized Loss Position [Line Items]    
Less than 12 Months, Fair Value 14,349 4,230
Less than 12 Months, Unrealized Loss (85) (9)
12 Months or Greater, Fair Value 890 1,174
12 Months or Greater, Unrealized Loss (16) (17)
Total Fair Value 15,239 5,404
Total Unrealized Loss (101) (26)
Corporate debt securities    
Investments, Unrealized Loss Position [Line Items]    
Less than 12 Months, Fair Value 5,506 915
Less than 12 Months, Unrealized Loss (17) 0
12 Months or Greater, Fair Value 1,826 2,429
12 Months or Greater, Unrealized Loss (19) (24)
Total Fair Value 7,332 3,344
Total Unrealized Loss (36) (24)
Mortgage-backed and asset-backed securities    
Investments, Unrealized Loss Position [Line Items]    
Less than 12 Months, Fair Value 5,228 1,377
Less than 12 Months, Unrealized Loss (40) (4)
12 Months or Greater, Fair Value 1,972 3,035
12 Months or Greater, Unrealized Loss (120) (124)
Total Fair Value 7,200 4,412
Total Unrealized Loss $ (160) $ (128)