Employee Stock Plans - Assumption used with Black Scholes Option Valuations Models (Details) - NAREIT Lodging & Resorts Index - $ / shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
2020 Award Grants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Market price per Host Inc. common share	$ 10.06
Volatility	33.10%
Beta	0.618
2020 Award Grants \| Three Year Award
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free rate	0.19%
2019 Award Grants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Market price per Host Inc. common share		$ 17.97
Volatility		23.70%
Beta		1.029
2019 Award Grants \| Three Year Award
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free rate		2.43%

Share based compensation arrangement by share based payment award fair value assumptions beta.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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Rate of weighted-average expected volatility for award under share-based payment arrangement.

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-Name Accounting Standards Codification
-Topic 718
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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