Summary of Significant Accounting Policies (Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Investment available for sale	$ 15,300	$ 17,300
Available-for-sale securities, current portion	500	500
Peninsula Gaming
Debt Securities, Available-for-sale [Line Items]
Investment available for sale	$ 15,800	17,800
Peninsula Gaming \| 7.5% City Bonds
Debt Securities, Available-for-sale [Line Items]
Debt security, interest rate	7.50%
Available-for-sale securities, current portion	$ 510	500
(In thousands)
2014	550
2015	590
2016	635
2017	680
Thereafter	17,080
Total	20,045
Peninsula Gaming \| Other Assets, Net
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, noncurrent portion	$ 15,300	$ 17,300

Available-for-sale Securities, Debt Maturities, after Five Years, Fair Value

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- Definition

Available-for-sale Securities, Debt Maturities, Year Five, Fair Value

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Available-for-sale Securities, Debt Maturities, Year Four, Fair Value

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Available-for-sale Securities, Debt Maturities, Year Three, Fair Value

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Available-for-sale Securities, Debt Maturities, Year Two, Fair Value

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Debt Security, Interest Rate, Stated Percentage

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- Definition

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

+ References

No definition available.

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Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

+ References

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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