Fair Value Measurements (Fair Value, by Balance Sheet Grouping) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Parent \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Commitments, Fair Value Disclosure	$ 34,655	$ 35,126
Other Financial Instruments	200	200
Parent \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Commitments, Fair Value Disclosure	27,357	27,660
Other Financial Instruments	189	186
Parent \| Fair Value, Inputs, Level 3 [Member] \| 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	28,282	28,381
Other Financial Instruments	189	186
Peninsula Gaming
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment available for sale	18,000	17,400
Business Combination, Contingent Consideration, Liability for Payments to Option Holder, Current	900	900
Business Combination, Contingent Consideration, Liability for Payments to Option Holder, Noncurrent	$ 2,700	$ 2,700

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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Other Financial Instruments, Liabilities, Fair Value Disclosure

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26610-111562

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 19
-Article 7

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 17
-Article 9

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