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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($) GroundLease	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) GroundLease	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Significant Accounting Policies [Line Items]
Cumulative effect of new accounting principle in period of adoption	$ 0		$ 0
Total assets, adjustment applied due to new accounting principle in period of adoption	11,542,000,000		11,542,000,000		$ 11,656,000,000
Total liabilities, adjustment applied due to new accounting principle in period of adoption	4,274,000,000		4,274,000,000		4,409,000,000
Change on total revenues due to new accounting principle in period of adoption	1,295,000,000	$ 1,283,000,000	4,093,000,000	$ 4,024,000,000
Advances to and investments in affiliates	307,000,000		307,000,000		324,000,000
Variable Interest Entities
Significant Accounting Policies [Line Items]
Total assets of VIE	61,000,000		61,000,000
Liabilities of VIE	$ 3,000,000		$ 3,000,000
HOST HOTELS & RESORTS, INC.
Significant Accounting Policies [Line Items]
Percentage of the common OP units	99.00%		99.00%
Philadelphia Marriott Downtown \| Limited Partnership Interests Of Parent Company Ownership
Significant Accounting Policies [Line Items]
General partner and limited partner interest			11.00%
General Partner \| HOST HOTELS & RESORTS, INC.
Significant Accounting Policies [Line Items]
Percentage of the common OP units	99.00%		99.00%
General Partner \| Houston Airport Marriott
Significant Accounting Policies [Line Items]
General partner and limited partner interest			85.00%
Fort Lauderdale Marriott Harbor Beach Resort \| General Partner
Significant Accounting Policies [Line Items]
Investment ownership percentage	49.90%		49.90%
ASU 2016-02
Significant Accounting Policies [Line Items]
Number of ground leases \| GroundLease	26		26
Percentage of operating lease payments	85.00%		85.00%
ASU 2015-02
Significant Accounting Policies [Line Items]
Change on net income due to new accounting principle in period of adoption		2,000,000		(5,000,000)
Effect on equity due to new accounting principle in period of adoption	$ 0		$ 0
ASU 2015-02 \| Variable Interest Entities Not Primary Beneficiary
Significant Accounting Policies [Line Items]
Advances to and investments in affiliates	$ (7,000,000)		(7,000,000)
ASU 2015-02 \| Restatement Adjustment
Significant Accounting Policies [Line Items]
Total assets, adjustment applied due to new accounting principle in period of adoption					(128,000,000)
Total liabilities, adjustment applied due to new accounting principle in period of adoption					$ (150,000,000)
Change on total revenues due to new accounting principle in period of adoption		$ (4,000,000)		$ (29,000,000)
Minimum \| Asset \| ASU 2016-02
Significant Accounting Policies [Line Items]
Right of use asset and operating lease liability			400,000,000
Minimum \| Liability \| ASU 2016-02
Significant Accounting Policies [Line Items]
Right of use asset and operating lease liability			400,000,000
Maximum \| Asset \| ASU 2016-02
Significant Accounting Policies [Line Items]
Right of use asset and operating lease liability			500,000,000
Maximum \| Liability \| ASU 2016-02
Significant Accounting Policies [Line Items]
Right of use asset and operating lease liability			$ 500,000,000