Equity Investments - Northstar New Jersey (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Equity Method Investments [Line Items]
Payments to equity method investment	$ 48.2	$ 86.1	$ 0
Earnings (loss) from equity investments	(7.6)	1.5	28.1
Northstar New Jersey
Schedule of Equity Method Investments [Line Items]
Equity interest (as a percent)	17.69%
Investee payment to third party	120.0
Contribution to investee	21.5
Contribution of working capital		7.2
Incentive compensation cap, percentage of net income	5.00%
Investee payment to third party cap, percentage of net income	2.00%
Investee payment to third party, shortfall credit	20.0
Revenue from the sale of instant tickets to equity method investment	12.7	1.2
Accounts receivable from equity method investment	3.1
Northstar SupplyCo New Jersey, LLC
Schedule of Equity Method Investments [Line Items]
Equity interest (as a percent)	30.00%
Economic interest	30.00%
Capital requirements, percentage	30.00%
Payments to equity method investment	3.7
Northstar New Jersey and Northstar SupplyCo
Schedule of Equity Method Investments [Line Items]
Earnings (loss) from equity investments	$ 3.7	$ 0.9

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