v2.4.0.6
Employee Benefit Plans (Details) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Contributions based on wages paid to covered employees $ 8.1 $ 7.1 $ 7.1
Voluntary contributions to the 401(k) profit-sharing plans and trusts 5.3 5.1 5.1
Borgata
     
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Multiemployer plan, employer share of unfunded liabilities     $ 68.3