Ground leases, as percentage of annual operating lease payments.

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Significant accounting policies.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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Number of separate real estate development properties located on land subject to ground leases.

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Summary of Significant Accounting Policies - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2018 USD ($) GroundLease	Jan. 01, 2018 USD ($)
ASU 2016-02
Significant Accounting Policies [Line Items]
Number of ground leases \| GroundLease	25
Percentage of annual operating lease payments	85.00%
ASU 2016-02 \| Asset \| Minimum
Significant Accounting Policies [Line Items]
Adjustment applied due to new accounting principle in period of adoption	$ 500,000,000
ASU 2016-02 \| Asset \| Maximum
Significant Accounting Policies [Line Items]
Adjustment applied due to new accounting principle in period of adoption	600,000,000
ASU 2016-02 \| Liability \| Minimum
Significant Accounting Policies [Line Items]
Adjustment applied due to new accounting principle in period of adoption	500,000,000
ASU 2016-02 \| Liability \| Maximum
Significant Accounting Policies [Line Items]
Adjustment applied due to new accounting principle in period of adoption	$ 600,000,000
ASU No. 2014-09
Significant Accounting Policies [Line Items]
Adoption of revenue recognition, description	We adopted these standards using a modified retrospective approach with a cumulative effect recognized in our equity balance on the date of adoption and no restatements of prior period amounts. When applying the new standard for the cumulative effect, we elected to apply the new standard only to contracts that were not considered completed as of the date of adoption.
Decrease in total liabilities		$ 4,500,000
Increase in total equity		$ 4,500,000
HOST HOTELS & RESORTS, INC.
Significant Accounting Policies [Line Items]
Percentage of the common OP units	99.00%
HOST HOTELS & RESORTS, INC. \| Sole General Partner \| Variable Interest Entities
Significant Accounting Policies [Line Items]
Percentage of the common OP units	99.00%