Host Inc. Earnings (Loss) Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Abstract]
NET INCOME	$ 212	$ 351	$ 373	$ 535
Less: Net income attributable to non-controlling interests	(2)	(4)	(5)	(6)
NET INCOME ATTRIBUTABLE TO REPORTING ENTITY	$ 210	$ 347	$ 368	$ 529
Basic weighted average shares outstanding	738.6	744.0	738.3	746.8
Assuming distribution of common shares granted under the comprehensive stock plans, less shares assumed purchased at market	0.2	0.3	0.2	0.3
Diluted weighted average shares/units outstanding	738.8	744.3	738.5	747.1
Basic earnings per common share	$ 0.28	$ 0.47	$ 0.50	$ 0.71
Diluted earnings per common share	$ 0.28	$ 0.47	$ 0.50	$ 0.71