Accumulated Other Comprehensive Loss - Reclassifications (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Reclassifications out of accumulated other comprehensive income loss by component
Other income, net	$ (28)	$ (194)	$ (58)	$ (267)
Total before tax	1,149	41	1,394	(61)
Income tax (benefit) expense	(234)	8	(278)	53
Net of tax	915	49	1,116	(8)
Decrease (Increase) in Net Income | Defined Benefit Plan
Reclassifications out of accumulated other comprehensive income loss by component
Total before tax	28	18	55	38
Income tax (benefit) expense	(7)	(4)	(14)	(9)
Net of tax	21	14	41	29
Decrease (Increase) in Net Income | Net actuarial loss
Reclassifications out of accumulated other comprehensive income loss by component
Other income, net	30	21	59	45
Decrease (Increase) in Net Income | Prior service credit
Reclassifications out of accumulated other comprehensive income loss by component
Other income, net	$ (2)	$ (3)	$ (4)	$ (7)