Business Segments - Segment Profits (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment profits	$ 740	$ 744	$ 1,240	$ 1,290
Interest expense, net of interest income	(79)	(65)	(149)	(128)
Income taxes	(186)	(227)	(290)	(350)
NET INCOME	610	489	1,008	860
Total segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment profits	946	804	1,676	1,505
Other unallocated corporate
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment profits	(71)	(23)	(229)	(167)
North American Full-Service \| Total segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment profits	394	375	671	677
North American Limited-Service \| Total segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment profits	252	243	434	430
Asia Pacific \| Total segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment profits	140	73	252	167
Other International \| Total segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment profits	$ 160	$ 113	$ 319	$ 231

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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