Pension Benefit Plans (Disaggregation of Service Costs) (Details) - Pension benefit plans - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ (40)	$ (31)	$ (32)
Other income (expense), net	19	15	37
Total	(21)	(16)	5
Cost of sales
Defined Benefit Plan Disclosure [Line Items]
Service cost	(7)	(6)	(11)
Selling, general and administrative expenses
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ (33)	$ (25)	$ (21)