Summary of Hotel Revenues by Market Locations (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation Of Revenue [Line Items]
Total revenues	$ 1,299	$ 1,254	$ 4,163	$ 4,043
New York
Disaggregation Of Revenue [Line Items]
Total revenues	172	193	539	554
San Diego
Disaggregation Of Revenue [Line Items]
Total revenues	136	131	402	394
San Francisco/San Jose
Disaggregation Of Revenue [Line Items]
Total revenues	131	106	373	313
Maui/Oahu
Disaggregation Of Revenue [Line Items]
Total revenues	93	70	270	215
Washington, D.C. (Central Business District)
Disaggregation Of Revenue [Line Items]
Total revenues	71	76	252	270
Boston
Disaggregation Of Revenue [Line Items]
Total revenues	86	83	231	231
Phoenix
Disaggregation Of Revenue [Line Items]
Total revenues	46	35	220	195
Florida Gulf Coast
Disaggregation Of Revenue [Line Items]
Total revenues	37	35	216	189
Orlando
Disaggregation Of Revenue [Line Items]
Total revenues	44	39	170	156
Los Angeles
Disaggregation Of Revenue [Line Items]
Total revenues	48	51	143	139
Chicago
Disaggregation Of Revenue [Line Items]
Total revenues	53	54	140	138
Atlanta
Disaggregation Of Revenue [Line Items]
Total revenues	37	37	119	122
Northern Virginia
Disaggregation Of Revenue [Line Items]
Total revenues	34	44	115	144
Seattle
Disaggregation Of Revenue [Line Items]
Total revenues	38	38	99	99
Orange County
Disaggregation Of Revenue [Line Items]
Total revenues	32	31	91	92
Houston
Disaggregation Of Revenue [Line Items]
Total revenues	25	24	88	87
San Antonio
Disaggregation Of Revenue [Line Items]
Total revenues	26	23	86	83
Jacksonville
Disaggregation Of Revenue [Line Items]
Total revenues	25	21	78	72
New Orleans
Disaggregation Of Revenue [Line Items]
Total revenues	19	17	75	71
Denver
Disaggregation Of Revenue [Line Items]
Total revenues	26	25	69	67
Philadelphia
Disaggregation Of Revenue [Line Items]
Total revenues	22	19	65	59
Miami
Disaggregation Of Revenue [Line Items]
Total revenues	9	9	41	40
Other
Disaggregation Of Revenue [Line Items]
Total revenues	61	64	196	217
United States
Disaggregation Of Revenue [Line Items]
Total revenues	1,271	1,225	4,078	3,947
International
Disaggregation Of Revenue [Line Items]
Total revenues	$ 28	$ 29	$ 85	$ 96