Discontinued Operations - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended	1 Months Ended
Dec. 31, 2012 Hotel	Dec. 31, 2011 Hotel	Dec. 31, 2010 Hotel	Jan. 11, 2013 Subsequent Event Atlanta Marriott Marquis Room
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of hotels sold	3	1	2
Number of rooms				1,663
Sale price				$ 293
Proceeds from sale of assets				276
FF&E				17
Gain on sale	48		(2)	21
Deferred for an environmental contingency				$ 5

Number of Hotels Sold

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- Definition

Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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- Definition

Total anticipated costs associated with remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal, or abandonment of a particular property resulting from unanticipated contamination of the assets.

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- Definition

The number of units in a real estate property owned as of the balance sheet date.

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This element represents the cash inflow during the period from the sale of a component of the entity.

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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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This element represents those amounts set aside for the repair and replacement of real or personal property in the foreseen future. Such amount may be funded from sales revenue (for example; timeshare sales) or operating revenues; in a lump sum or installments (such as monthly); as per internal policy (for example: hotel operators), as required by contractual agreement (for example: sales contract); or by the terms of debt agreements.

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