Income Tax Provision Calculated at Statutory U.S. Federal Income Tax Rate and Actual Income Tax Provision Recorded (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Statutory federal income tax provision – continuing operations	$ 265	$ 81	$ 8
Adjustment for nontaxable (income) loss of Host Inc. – continuing operations	(268)	(77)	4
State income tax provision, net	1	5	2
Provision for uncertain tax positions	5	2	2
Foreign income tax provision	11	10	15
Income tax provision – continuing operations	$ 14	$ 21	$ 31