Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
AOCI, Translation adjustments, net of tax	$ (39)			$ (39)		$ (38)
AOCI, Post-retirement benefits and other, net of tax	(50)			(50)		(50)
Accumulated other comprehensive loss, net of tax	(89)			(89)		$ (88)
Other comprehensive income (loss), translation adjustments, before reclassification adjustment, net of tax				(2)
Other comprehensive income (loss), post-retirement benefits, before reclassification adjustment, net of tax				0
Other comprehensive income (loss), before reclassification adjustment, net of tax				(2)
Other comprehensive income, translation adjustments, gain (loss), reclassification from AOCI, net of tax				1
Other comprehensive income (loss), post-retirement benefits, gain (loss), reclassification adjustment from AOCI, after Tax				0
Other comprehensive income, gain (loss) reclassification adjustment from AOCI, net of tax				1
Other comprehensive loss, translation adjustments, net of tax	2			(1)	$ (1)
Other comprehensive income (loss), post-retirement benefits, net of tax			$ 1	0	2
Other comprehensive loss, net of tax	$ 2	$ (3)	$ 1	$ (1)	$ 1