Summary of Unaudited Consolidated Pro Forma Results of Operations (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Business Acquisition, Pro Forma Information [Abstract]
Revenues	$ 5,362	$ 5,189
Income from continuing operations	751	214
Net income	751	329
HOST HOTELS & RESORTS, INC.
Business Acquisition, Pro Forma Information [Abstract]
Net income attributable to Host Inc.	736	321
Basic earnings per common share:
Continuing operations	$ 0.97	$ 0.27
Discontinued operations		$ 0.16
Basic earnings per common share	$ 0.97	$ 0.43
Diluted earnings per common share:
Continuing operations	$ 0.97	$ 0.28
Discontinued operations		$ 0.15
Diluted earnings per common share	$ 0.97	$ 0.43
HOST HOTELS & RESORTS L.P.
Business Acquisition, Pro Forma Information [Abstract]
Net income attributable to Host Inc.	$ 745	$ 325
Basic earnings per common share:
Continuing operations	$ 0.99	$ 0.29
Discontinued operations		$ 0.15
Basic earnings per common share	$ 0.99	$ 0.44
Diluted earnings per common share:
Continuing operations	$ 0.99	$ 0.29
Discontinued operations		$ 0.15
Diluted earnings per common share	$ 0.99	$ 0.44

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The pro forma income from discontinued operations per basic share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

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No definition available.

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The pro forma income from discontinued operations per diluted share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

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No definition available.

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The pro forma net Income or Loss for the period attributable to the parent entity as if the business combination or combinations had been completed at the beginning of a period.

+ References

No definition available.

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, per diluted share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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