Pension, Savings and Other Postretirement Benefit Plans - Defined Benefit Pension Cost (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
U.S.
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Type [Extensible List]	Pension Plan	Pension Plan
Service cost	$ 1	$ 1
Interest cost	20	33
Expected return on plan assets	(42)	(49)
Amortization of net losses	28	27
Net periodic pension cost	7	12
Net curtailments/settlements/termination benefits		1
Total defined benefit pension cost	$ 7	$ 13
Non-U.S.
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Type [Extensible List]	Pension Plan	Pension Plan
Service cost	$ 7	$ 7
Interest cost	11	14
Expected return on plan assets	(10)	(14)
Amortization of prior service cost		1
Amortization of net losses	8	10
Net periodic pension cost	16	18
Net curtailments/settlements/termination benefits		1
Total defined benefit pension cost	$ 16	$ 19