Income Tax Provision Calculated at Statutory U.S. Federal Income Tax Rate and Actual Income Tax Provision Recorded (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Statutory federal income tax provision	$ 273	$ 228	$ 284
Adjustment for nontaxable income of Host Inc.	(192)	(190)	(260)
State income tax provision, net	31	10	7
Remeasurement of domestic net deferred tax assets		11
Foreign income tax provision	38	21	9
Income tax provision – continuing operations	$ 150	$ 80	$ 40