Summary of Investments in Affiliates (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Nov. 09, 2012
Schedule Of Investments [Line Items]
Advances to and investments in affiliates	$ 433	$ 415
Our Portion of Debt	502hst_DebtAttributableToParent	500hst_DebtAttributableToParent
Total Debt	1,577us-gaap_LongTermDebt	1,476us-gaap_LongTermDebt
European Joint Venture
Schedule Of Investments [Line Items]
Advances to and investments in affiliates	348	374
Our Portion of Debt	388	444
Total Debt	1,186	1,363
Assets	Nineteen hotels in Europe	Nineteen hotels in Europe
European Joint Venture \| Lower Limit
Schedule Of Investments [Line Items]
Investment ownership percentage	32.10%	32.10%
European Joint Venture \| Upper Limit
Schedule Of Investments [Line Items]
Investment ownership percentage	33.40%	33.40%
Asia/Pacific Joint Venture
Schedule Of Investments [Line Items]
Investment ownership percentage	25.00%	25.00%
Advances to and investments in affiliates	22	20
Our Portion of Debt	9	10
Total Debt	37	39
Assets	One hotel in Australia and a 36% interest in three operating hotels and four hotels under development in India	One hotel in Australia and a 36% interest in two operating hotels and five hotels under development in India
Maui JV
Schedule Of Investments [Line Items]
Investment ownership percentage	67.00%	67.00%	67.00%
Advances to and investments in affiliates	61	16	8
Our Portion of Debt	64	34
Total Debt	96	50
Assets	131-unit vacation ownership project in Maui, Hawaii	131-unit vacation ownership project in Maui, Hawaii
Hyatt Place JV
Schedule Of Investments [Line Items]
Investment ownership percentage	50.00%	50.00%
Advances to and investments in affiliates	7	5
Our Portion of Debt	16	12
Total Debt	31	24
Assets	One hotel in Nashville, Tennessee	One hotel in Nashville, Tennessee
Philadelphia Marriott Downtown
Schedule Of Investments [Line Items]
Investment ownership percentage	11.00%
Advances to and investments in affiliates	(5)
Our Portion of Debt	25
Total Debt	$ 227
Assets	One hotel in Philadelphia, PA

Affiliates' portion of debt that is attributable to the reporting entity.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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