Host Inc. Earnings (Loss) Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Earnings Per Share [Abstract]
Net income (loss)	$ 118	$ (153)
Less: Net (income) loss attributable to non-controlling interests	(2)	1
NET INCOME (LOSS) ATTRIBUTABLE TO HOST HOTELS & RESORTS, INC.	$ 116	$ (152)
Basic weighted average shares outstanding	714.3	705.6
Assuming distribution of common shares granted under the comprehensive stock plans, less shares assumed purchased at market	1.8	0.0
Diluted weighted average shares outstanding	716.1	705.6
Basic earnings (loss) per common share	$ 0.16	$ (0.22)
Diluted earnings (loss) per common share	$ 0.16	$ (0.22)