Business Segments - Segment Revenues (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 5,663	$ 3,942	$ 17,019	$ 11,616
Total segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	5,522	3,703	16,582	11,250
Other unallocated corporate
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	141	239	437	366
North American Full-Service | Total segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	3,436	2,222	10,631	6,903
North American Limited-Service | Total segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	1,061	936	3,017	2,675
Asia Pacific | Total segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	337	141	968	428
Other International | Total segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 688	$ 404	$ 1,966	$ 1,244