Retirement Programs - Schedule of Pension and OPEB Net Periodic Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Amount recognized in Net pension and OPEB cost (benefit), excluding service cost
Net pension and OPEB cost (benefit)	$ (64)	$ (49)
Pension Plan
Amount recognized in Operating Profit
Service cost	33	40
Amount recognized in Net pension and OPEB cost (benefit), excluding service cost
Interest cost	53	39
Expected return on plan assets	(136)	(131)
Net amortization and deferral	19	43
Net pension and OPEB cost (benefit)	(64)	(49)
Net periodic benefit cost (benefit)	$ (31)	$ (9)