Acquisitions, Investments and Dispositions (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Assets
Assets held for sale, current	$ 11.1	$ 11.6
Harrah's St. Louis Casino [Member]
Assets
Cash and cash equivalents	9.6	10.0
Other current assets	1.5	1.6
Assets held for sale, current	11.1	11.6
Property and equipment, net	194.9	196.1
Goodwill	104.4	104.4
Intangible assets other than goodwill	292.7	292.7
Other long-term assets	0.3	0.2
Assets held for sale, non-current	592.3	593.4
Liabilities
Accounts payable and accrued expenses	9.6	10.1
Liabilities held for sale, current	$ 9.6	$ 10.1

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Current assets (normally turning over within one year or one business cycle if longer) that are held for sale apart from normal operations and anticipated to be sold within one year.

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Long-lived assets that are held for sale apart from normal operations and anticipated to be sold in less than one year.

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For the disposal group, including a component of the entity (discontinued operation), carrying value of obligations incurred and payable pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include interest, rent, salaries, and utilities.

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For the disposal group, including a component of the entity (discontinued operation), cash includes currency on hand as well as demand deposits with banks or financial institutions. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

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For the disposal group, including a component of the entity (discontinued operation), carrying amount of goodwill (adjusted for any amortization recognized prior to adoption of FAS 142 and impairment charges).

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For the disposal group, including a component of the entity (discontinued operation), carrying value (net of any accumulated amortization and write-downs) of nonphysical assets (such as copyrights, customer lists, patents, trade names, core deposits, trade secrets, and contractual rights), not elsewhere itemized.

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For the disposal group, including a component of the entity (discontinued operation), carrying amount of assets not otherwise specified in the taxonomy that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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For the disposal group, including a component of the entity (discontinued operation), carrying value (net of accumulated depreciation and any write-downs) of tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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Liability (such as a mortgage) related to a disposal group that is held for sale and anticipated to be sold in less than one year. The liability is expected to be discharged as part of the plan of sale for the asset.

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