Equity Investments - Schedules of Equity Method Investments (Details) - USD ($) $ in Millions	1 Months Ended		12 Months Ended
	Jan. 31, 2011	Oct. 31, 2010	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Equity Method Investments [Line Items]
Equity investments			$ 253.9	$ 179.9
Earnings from equity investments			26.7	13.0	$ 16.9
Distributed earnings from equity investments			67.3	51.7	63.6
Revenue from the sale of instant tickets to equity method investment			95.0	93.7	91.7
Equity Method Investments, Excluding Fair Value Accounting Method
Schedule of Equity Method Investments [Line Items]
Equity investments			163.5	179.9
Earnings from equity investments			26.7	13.0	16.9
Distributed earnings from equity investments			67.3	51.7	63.6
LNS
Schedule of Equity Method Investments [Line Items]
Revenue from the sale of instant tickets to equity method investment			44.9	45.3	46.6
LNS | Equity Method Investments, Excluding Fair Value Accounting Method
Schedule of Equity Method Investments [Line Items]
Equity investments			75.1	80.0
Earnings from equity investments			14.3	14.0	14.8
Distributed earnings from equity investments			40.4	34.3	31.5
Northstar IL
Schedule of Equity Method Investments [Line Items]
Revenue from the sale of instant tickets to equity method investment			22.8	22.6	20.8
Northstar IL | Equity Method Investments, Excluding Fair Value Accounting Method
Schedule of Equity Method Investments [Line Items]
Equity investments			0.0	0.0
Earnings from equity investments			2.8	(0.4)	(2.7)
Distributed earnings from equity investments			0.0	0.0	0.0
Northstar NJ and NJ Supply Co
Schedule of Equity Method Investments [Line Items]
Revenue from the sale of instant tickets to equity method investment			20.6	20.9	18.3
Northstar NJ and NJ Supply Co | Equity Method Investments, Excluding Fair Value Accounting Method
Schedule of Equity Method Investments [Line Items]
Equity investments			21.2	24.8
Earnings from equity investments			0.9	1.0	(4.0)
Distributed earnings from equity investments			4.6	4.8	0.0
GLB and CSG | Equity Method Investments, Excluding Fair Value Accounting Method
Schedule of Equity Method Investments [Line Items]
Equity investments			35.3	38.3
Earnings from equity investments			(0.1)	(8.0)	3.5
Distributed earnings from equity investments			5.0	1.7	4.7
International Terminal Leasing | Equity Method Investments, Excluding Fair Value Accounting Method
Schedule of Equity Method Investments [Line Items]
Equity investments			8.1	12.3
Earnings from equity investments			0.8	0.0	1.0
Distributed earnings from equity investments			5.6	5.9	10.0
Other
Schedule of Equity Method Investments [Line Items]
Revenue from the sale of instant tickets to equity method investment			6.7	4.9	6.0
Other | Equity Method Investments, Excluding Fair Value Accounting Method
Schedule of Equity Method Investments [Line Items]
Equity investments			23.8	24.5
Earnings from equity investments			8.0	6.4	4.3
Distributed earnings from equity investments			11.7	5.0	17.4
NYX
Schedule of Equity Method Investments [Line Items]
Equity investments			90.4	0.0
Earnings from equity investments			0.0	0.0	0.0
Distributed earnings from equity investments			$ 0.0	$ 0.0	$ 0.0
Corporate | NYX
Schedule of Equity Method Investments [Line Items]
Equity interest (as a percent)			36.00%
Lottery | LNS
Schedule of Equity Method Investments [Line Items]
Agreement term		9 years
Equity interest (as a percent)			20.00%
Lottery | Northstar IL
Schedule of Equity Method Investments [Line Items]
Agreement term	10 years
Equity interest (as a percent)			20.00%
Lottery | Northstar NJ
Schedule of Equity Method Investments [Line Items]
Equity interest (as a percent)			17.69%
Lottery | Northstar SupplyCo New Jersey, LLC
Schedule of Equity Method Investments [Line Items]
Equity interest (as a percent)			30.00%