Estimated Fair Value of the Assets Acquired and Liabilities Assumed in our Acquisitions (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Business Acquisition [Line Items]
Property and equipment	$ 1,174	$ 557
Goodwill		13
Intangible asset	7
Deferred tax asset	10	17
Restricted cash, FF&E reserve and other assets	20	24
Total assets	1,211	611
Mortgage debt	(86)	(168)
Capital lease obligation		(58)
Deferred tax liability	(13)	(30)
Other liabilities	(6)	(13)
Net assets acquired	$ 1,106	$ 342

Business Acquisition, Purchase Price Allocation, Deferred Income Tax Asset

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

+ References

+ Details

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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

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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.

+ References

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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

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 98-1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 37

-Subparagraph g

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 53

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The amount of acquisition cost of a business combination allocated to other noncurrent liabilities of the acquired entity.

+ References

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- Definition

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

+ References

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