Property and Equipment, net (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Property, Plant and Equipment [Abstract]
Land and land improvements	$ 7,095.6	$ 7,208.8
Buildings, riverboats, and improvements	8,572.0	8,725.7
Furniture, fixtures, and equipment	2,567.8	2,491.0
Construction in progress	579.4	378.3
Total, Gross	18,814.8	18,803.8
Less: accumulated depreciation	(3,352.9)	(3,102.1)
Property and equipment, net	$ 15,461.9	$ 15,701.7

The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 5

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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- Definition

Gross amount, at the balance sheet date, of long-lived assets under construction that include construction costs to date on capital projects that have not been completed and assets being constructed that are not ready to be placed into service.

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- Definition

Gross amount, at the balance sheet date, of long-lived, depreciable assets commonly used in offices and stores. Examples include desks, chairs, and store fixtures.

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- Definition

Carrying amount of real estate held for productive use and alterations to land which improves its potential for use, examples include, but are not limited to, walkways, driveways, fences, and parking lots. Excludes land held for sale.

+ References

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

-Publisher FASB

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Gross amount of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount, net of accumulated depreciation, depletion and amortization, of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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

-Publisher FASB

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-Publisher FASB

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-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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