Host Inc. Earnings Per Common Share (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Earnings Per Share Diluted [Line Items]
Net income	$ 159		$ 121		$ 344		$ 181
Less: Net income attributable to non-controlling interests	(4)		(2)		(10)		(6)
Net income attributable to Host Inc.	155		119		334		175
Diluted income attributable to Host Inc.	$ 155		$ 119		$ 334		$ 175
Basic weighted average shares outstanding	755.4		745.2		755.1		736.8
Assuming weighted average shares for conversion of exchangeable senior debentures							4.9
Assuming distribution of common shares granted under the comprehensive stock plans, less shares assumed purchased at market	0.5		0.7		0.5		0.7
Diluted weighted average shares outstanding	755.9	[1]	745.9	[1]	755.6	[1]	742.4	[1]
Basic earnings per common share	$ 0.21		$ 0.16		$ 0.44		$ 0.24
Diluted earnings per common share	$ 0.21		$ 0.16		$ 0.44		$ 0.24

[1] There were approximately 30 million potentially dilutive shares for both the quarter and year-to-date periods ended June 30, 2014, and approximately 29 million potentially dilutive shares for both the quarter and year-to-date periods ended June 30, 2013, related to our exchangeable senior debentures, which shares were not included in the computation of diluted earnings per share because to do so would have been anti-dilutive for the period. Income allocated to non-controlling interests of Host L.P. has been excluded from the numerator and common OP units in Host L.P. have been omitted from the denominator for the purpose of computing diluted earnings per share since the effect of including these amounts would have no impact.