Business Combination, Contingent Consideration Arrangements, Earnout Multiple

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Business Combination, Contingent Consideration Arrangements, Earnout Threshold, EBITDA of Certain Properties

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Business Combination, Contingent Consideration Arrangements, Payment to Option Holder, Percentage of EBITDA

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Business Combination, Contingent Consideration Arrangements, Payment to Option Holder, Term

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Business Combination, Contingent Consideration, Liability for Merger Earnout

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Business Combination, Contingent Consideration, Liability for Payments to Option Holder, Current

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Business Combination, Contingent Consideration, Liability for Payments to Option Holder, Noncurrent

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Fair Value Measurements (Narrative-Balances Measured at Fair Value) (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended
	Dec. 20, 2011	Mar. 31, 2015	Dec. 31, 2014
Kansas Star
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payment to Option Holder, Percentage of EBITDA	1.00%
Payment to Option Holder, Term	10 years
Merger Earnout \| Kansas Star
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earnout Threshold, EBITDA of Certain Properties		$ 105.0
Earnout Multiple		7.5
Peninsula Gaming
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent Consideration, Kansas Star earnout			0.1
Business Combination, Contingent Consideration, Liability for Payments to Option Holder, Current		0.9	0.9
Business Combination, Contingent Consideration, Liability for Payments to Option Holder, Noncurrent		$ 2.9	$ 2.9