Earnings (Loss) Per Common Share Or Unit (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share Diluted [Line Items]
NET INCOME (LOSS)	$ (741)	$ 932	$ 1,151
Less: Net (income) loss attributable to non-controlling interests	9	(12)	(64)
NET INCOME (LOSS) ATTRIBUTABLE TO HOST HOTELS & RESORTS, INC.	$ (732)	$ 920	$ 1,087
Basic weighted average shares outstanding	705.9	730.3	739.8
Assuming distribution of common shares granted under the comprehensive stock plans, less shares assumed purchased at market		0.8	0.8
Diluted weighted average shares/units outstanding	705.9	731.1	740.6
Basic earnings (loss) per common share	$ (1.04)	$ 1.26	$ 1.47
Diluted earnings (loss) per common share	$ (1.04)	$ 1.26	$ 1.47
HOST HOTELS & RESORTS L.P.
Earnings Per Share Diluted [Line Items]
NET INCOME (LOSS)	$ (741)	$ 932	$ 1,151
Less: Net (income) loss attributable to non-controlling interests	1	(2)	(52)
NET INCOME (LOSS) ATTRIBUTABLE TO HOST HOTELS & RESORTS, INC.	$ (740)	$ 930	$ 1,099
Basic weighted average shares outstanding	698.4	722.5	732.2
Assuming distribution of common shares granted under the comprehensive stock plans, less shares assumed purchased at market		0.8	0.8
Diluted weighted average shares/units outstanding	698.4	723.3	733.0
Basic earnings (loss) per common share	$ (1.06)	$ 1.29	$ 1.50
Diluted earnings (loss) per common share	$ (1.06)	$ 1.29	$ 1.50