Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended
Mar. 31, 2017 USD ($) GroundLease
ASU 2016-02
Significant Accounting Policies [Line Items]
Number of ground leases \| GroundLease	26
Percentage of 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	$ 400,000,000
ASU 2016-02 \| Asset \| Maximum
Significant Accounting Policies [Line Items]
Adjustment applied due to new accounting principle in period of adoption	500,000,000
ASU 2016-02 \| Liability \| Minimum
Significant Accounting Policies [Line Items]
Adjustment applied due to new accounting principle in period of adoption	400,000,000
ASU 2016-02 \| Liability \| Maximum
Significant Accounting Policies [Line Items]
Adjustment applied due to new accounting principle in period of adoption	$ 500,000,000
HOST HOTELS & RESORTS, INC.
Significant Accounting Policies [Line Items]
Percentage of the common OP units	99.00%
HOST HOTELS & RESORTS, INC. \| General Partner \| Variable Interest Entities
Significant Accounting Policies [Line Items]
Percentage of the common OP units	99.00%
Houston Airport Marriott at George Bush Intercontinental \| Variable Interest Entities
Significant Accounting Policies [Line Items]
Total assets of VIE	$ 60,000,000
Liabilities of VIE	$ 3,000,000
Houston Airport Marriott at George Bush Intercontinental \| General Partner
Significant Accounting Policies [Line Items]
General partner and limited partner interest	85.00%
Philadelphia Marriott Downtown \| Variable Interest Entities Not Primary Beneficiary
Significant Accounting Policies [Line Items]
Advances to and investments in affiliates	$ (7,000,000)
Philadelphia Marriott Downtown \| Limited Partnership Interests Of Parent Company Ownership
Significant Accounting Policies [Line Items]
General partner and limited partner interest	11.00%

Ground leases, as percentage of operating lease payments.

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Investments in and advances to affiliates at carrying amount.

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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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- Definition

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

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The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
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