Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 104	$ 73	$ 260	$ 210
Other comprehensive income (loss), before tax:
Foreign currency translation adjustment	7	(8)	66	(25)
Net change in derivative hedge agreements:
Unrealized (loss) gains	(1)	0	4	0
Amount of gain reclassified into net income	0	(1)	0	(2)
Net change in postretirement benefit plans:
Amortization of net actuarial loss into net income	3	3	8	8
Settlement/Curtailment	1	0	1	0
Other comprehensive income (loss), before tax	10	(6)	79	(19)
Income tax benefit related to items of other comprehensive income	(11)	(3)	(40)	(2)
Other comprehensive income (loss), net of tax	21	(3)	119	(17)
Comprehensive income	$ 125	$ 70	$ 379	$ 193