Restructuring (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Restructuring accrual
Beginning balance, restructuring reserve	$ 45	$ 45
Net cash paid, principally severance and related benefits	(3)	(8)
Other, including foreign exchange translation	1	(3)
Ending balance, restructuring reserve	43	34
Employee Costs
Restructuring accrual
Beginning balance, restructuring reserve	38	32
Net cash paid, principally severance and related benefits	(3)	(8)
Other, including foreign exchange translation		(2)
Ending balance, restructuring reserve	35	22
Other Exit Costs
Restructuring accrual
Beginning balance, restructuring reserve	7	13
Other, including foreign exchange translation	1	(1)
Ending balance, restructuring reserve	$ 8	$ 12