v2.4.0.6
Summary of Significant Accounting Policies (Investment Available for Sale) (Details) (Peninsula Gaming, USD $)
In Millions, unless otherwise specified
Mar. 31, 2013
Schedule of Available-for-sale Securities [Line Items]  
Debt Security, Interest Rate, Stated Percentage 7.50%
Available-for-sale Securities $ 18.2
Available-for-sale Securities, Current 0.3
City Urban Renewal Tax Increment Revenue Bonds [Member]
 
Schedule of Available-for-sale Securities [Line Items]  
Available-for-sale Securities, Debt Securities 22.4
Other Assets [Member]
 
Schedule of Available-for-sale Securities [Line Items]  
Available-for-sale Securities, Noncurrent $ 17.9