Accumulated Other Comprehensive Income (Loss) - Components of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 1,256	$ 1,494
Other comprehensive loss before reclassifications	(10)	(5)
Reclassified from Accumulated other comprehensive loss to earnings	5	1
Ending balance	1,416	1,256
Gain (loss) on derivative instruments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0	0
Other comprehensive loss before reclassifications	(8)	(1)
Reclassified from Accumulated other comprehensive loss to earnings	3	1
Ending balance	(5)	0
Foreign currency translation gain (loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(86)	(82)
Other comprehensive loss before reclassifications	(2)	(4)
Reclassified from Accumulated other comprehensive loss to earnings	2	0
Ending balance	$ (86)	$ (86)