Segment Information - Schedule of Total Assets and Capital Expenditures by Operating Segment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 2,254.4	$ 2,277.4
Capital expenditures	54.7	43.5	$ 54.5
Racing
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	454.6	437.1
Capital expenditures	26.1	12.3	33.9
Casinos
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	628.7	631.3
Capital expenditures	13.9	18.8	7.7
TwinSpires
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	209.9	202.4
Capital expenditures	7.0	4.3	5.8
Big Fish Games
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	893.8	947.1
Capital expenditures	5.5	6.4	0.1
Other Investments
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	11.1	12.2
Capital expenditures	1.0	0.8	5.3
Corporate
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	56.3	47.3
Capital expenditures	$ 1.2	$ 0.9	$ 1.7