Fair Value Measurements (Fair Value, by Balance Sheet Grouping) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Parent \| Level 3 \| Fair Value, Measurements, Nonrecurring [Member] \| Outstanding Face Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Commitments, Fair Value Disclosure	$ 35,943	$ 36,749
Other Financial Instruments	200	300
Parent \| Level 3 \| Fair Value, Measurements, Nonrecurring [Member] \| Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Commitments, Fair Value Disclosure	28,139	28,612
Other Financial Instruments	178	268
Parent \| Level 3 \| Fair Value, Measurements, Nonrecurring [Member] \| Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Commitments, Fair Value Disclosure	28,157	29,529
Other Financial Instruments	178	268
Peninsula Gaming
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment available for sale	16,900	18,000
Business Combination, Contingent Consideration, Liability for Payments to Option Holder, Current	900	900
Business Combination, Contingent Consideration, Liability for Payments to Option Holder, Noncurrent	$ 2,800	$ 2,900

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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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

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Fair value portion of arrangements with third parties, including, but not limited to, operating lease arrangement and arrangement in which the entity has agreed to expend funds to procure goods or services, or has agreed to commit resources to supply goods or services.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Article 7

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 17

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