Restructuring Charges/Other - Restructuring Reserve (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restructuring And Related Activities [Abstract]
Balance, January 1		$ 32	$ 57	$ 161
Restructuring charges	[1]	25	14	20
Non-cash items	[2]	(6)	0	0
Payments		(11)	(39)	(124)
Balance, December 31		$ 40	$ 32	$ 57

[1] Includes severance and benefits, accelerated depreciation, changes in estimates or other exit costs.

[2] Reflects charges for impacts of accelerated depreciation and changes in exchange rates.