Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended					9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
AOCI, Translation adjustments, net of tax	$ (42)					$ (42)		$ (38)
AOCI, Post-retirement benefits and other, net of tax	(52)					(52)		(47)
Accumulated other comprehensive loss, net of tax	(94)					(94)		$ (85)
Other comprehensive income (loss), translation adjustments, before reclassification adjustment, net of tax						(4)
Other comprehensive income (loss), post-retirement benefits, before reclassification adjustment, net of tax						0
Other comprehensive income (loss), before reclassification adjustment, net of tax						(4)
Other comprehensive income, translation adjustments, gain (loss), reclassification from AOCI, net of tax						0
Other comprehensive income (loss), post-retirement benefits, gain (loss), reclassification adjustment from AOCI, after Tax						1
Other comprehensive income, gain (loss) reclassification adjustment from AOCI, net of tax						1
Other comprehensive loss, translation adjustments, net of tax	(3)		$ (11)			(4)	$ (86)
Other comprehensive income (loss), post-retirement benefits, net of tax	(1)		3			1	18
Other comprehensive loss, net of tax	$ (4)	$ 1	$ (8)	$ (103)	$ 43	(3)	$ (68)
Elimination of stranded tax effects resulting from tax legislation, translation adjustments and other						0
Elimination of stranded tax effects resulting from tax legislation, post-retirement benefits						(6)
Elimination of stranded tax effects resulting from tax legislation						$ (6)