Restructuring Accruals (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Restructuring accrual
Beginning balance, restructuring reserve	$ 85	$ 85
Charges		38
Write-down of assets to net realizable value		(9)
Net cash paid, principally severance and related benefits	(6)	(8)
Other, including foreign exchange translation	1	(2)
Ending balance, restructuring reserve	$ 80	104
Americas
Restructuring, Additional Information
Employee costs, asset impairments and other exit costs		25
Europe
Restructuring, Additional Information
Employee costs, asset impairments and other exit costs		$ 13