Summary of Significant Accounting Policies (Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Investment available for sale	$ 16,800	$ 17,400
Available-for-sale securities, current portion	400	400
Peninsula Gaming
Schedule of Available-for-sale Securities [Line Items]
Investment available for sale	$ 17,300	17,800
Available-for-sale securities, current portion		400
Peninsula Gaming \| 7.5% City Bonds
Schedule of Available-for-sale Securities [Line Items]
Debt security, interest rate	7.50%
(In thousands)
2013	$ 440
2014	475
2015	510
2016	550
2017	590
Thereafter	18,395
Total	20,960
Peninsula Gaming \| Other Assets, Net
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, noncurrent portion	$ 16,800	$ 17,400

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