Equity of Host Inc. and Capital of Host L.P. - Additional Information (Detail) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Aug. 05, 2019 USD ($)	May 31, 2018 USD ($)	Feb. 28, 2017 USD ($)
Stockholders Equity Note [Line Items]
Common stock, shares authorized	1,050,000,000	1,050,000,000
Common stock, par value | $ / shares	$ 0.01	$ 0.01
Common stock, shares outstanding	705,400,000	713,400,000
Dividend policy	The amount of any future dividends will be determined by Host Inc.’s Board of Directors.
Dividends taxable as REIT qualified	5.90%	63.40%
Dividends taxable as ordinary income	3.60%	33.70%
Dividends taxable as unrecaptured Section 1250 gain	46.60%	2.50%
Dividend taxable as long term capital gain	43.90%	0.40%
Dividends taxable as ordinary income deduction section 199A	20.00%	20.00%
Line of credit facility, dividend restrictions	based on the terms of the credit facility amendments, we are restricted to paying a quarterly common cash dividend of $0.01 per share or higher amounts to the extent necessary to allow Host Inc. to maintain REIT status or to avoid corporate income or excise taxes, until after the covenant waiver period expires following the second quarter of 2022
Lower Limit
Stockholders Equity Note [Line Items]
Percentage of annual taxable income Host Inc is required to distribute	90.00%
Host L.P.
Stockholders Equity Note [Line Items]
Investment ownership percentage	99.00%
Percentage of the common OP Units	1.00%
HOST HOTELS & RESORTS, INC.
Stockholders Equity Note [Line Items]
Common stock, shares authorized	1,050,000,000	1,050,000,000
Common stock, par value | $ / shares	$ 0.01	$ 0.01
Common stock, shares outstanding	705,400,000	713,400,000
Preferred stock, shares authorized	50,000,000	50,000,000
Preferred stock, no par value | $ / shares
Preferred stock, shares outstanding	0	0
Common OP units, outstanding	690,500,000	698,300,000
Common stock repurchase, authorized amount | $			$ 1,000	$ 500
Available shares for repurchase | $	$ 371
Shares repurchased, average price | $ / shares	$ 16.49	$ 17.37
Shares repurchased	8,900,000	27,800,000
Repurchase of common stock, amount | $	$ 147	$ 482
HOST HOTELS & RESORTS, INC. | Maximum [Member]
Stockholders Equity Note [Line Items]
Common stock repurchase, authorized amount | $					$ 500
HOST HOTELS & RESORTS L.P.
Stockholders Equity Note [Line Items]
Shares issuable upon conversion of one OP unit	1.021494	1.021494
Common OP units, outstanding	697,700,000	705,800,000