Goodwill and Intangible Assets - Schedule of Gross Carrying Value and Accumulated Impairment Losses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Goodwill	$ 5,095	$ 5,159	$ 5,160
Goodwill, Impairment Losses	104
Foreign currency translation	40	(1)
Ownership
Goodwill [Line Items]
Gross carrying value	0	438	439
Accumulated impairment losses	0	(340)	(340)
Goodwill	0	98	99
Goodwill, Foreign Currency Translation Gain (Loss), Gross	6	(1)
Goodwill, Impairment Loss, Gross	(444)
Goodwill, Impairment Loss, Accumulated Impairment Loss	340
Goodwill, Foreign Currency Translation Gain (Loss), Accumulated Impairment Loss	0	0
Goodwill, Impairment Losses	104
Foreign currency translation	6	(1)
Management and franchise
Goodwill [Line Items]
Accumulated impairment losses	0	0	0
Goodwill	5,095	5,061	$ 5,061
Goodwill, Impairment Losses	0
Foreign currency translation	$ 34	$ 0