Estimated Fair Value of the Assets Acquired and Liabilities Assumed in our Acquisitions (Detail) (USD $) In Millions	Dec. 31, 2010
Business Acquisition [Line Items]
Property and equipment	$ 1,721
Goodwill	13
Deferred tax asset	17
Restricted cash, FF&E reserve and other assets	43
Total assets	1,794
Mortgage debt	(254)
Capital lease obligation	(58)
Deferred tax liability	(30)
Other liabilities	(19)
Net assets acquired	$ 1,433

Business Acquisition, Purchase Price Allocation, Deferred Income Tax Asset

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Business Acquisition, Purchase Price Allocation, Net Deferred Tax Asset, Net Deferred Tax Liabilities

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Business Acquisition, Purchase Price Allocation, Other Liabilities

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- Definition

The acquisition fair value of mortage debt assumed from the acquired entity during a business combination.

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Business Acquisition Purchase Price Restricted Cash Furniture Fixtures And Equipment Reserve And Other Assets

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The amount of acquisition cost of a business combination allocated to assets acquired.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 37
-Subparagraph g

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The total purchase price of the acquired entity. This includes cash paid to equity interest holders of the acquired entity, fair value of debt and equity securities issued to equity holders of the acquired entity, and transaction costs paid to third parties to consummate the acquisition.

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- Definition

The amount of acquisition cost of a business combination allocated to capital lease obligations assumed from the acquired entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 37
-Subparagraph g

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 98-1

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 52
-Subparagraph c

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 53
-Subparagraph d

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

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