Accounts Receivable - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net of allowance for doubtful accounts of $3.5 in 2016 and $3.8 in 2015	$ 81.4	$ 67.8
Big Fish Games
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net of allowance for doubtful accounts of $3.5 in 2016 and $3.8 in 2015	24.7	25.7
TwinSpires
Accounts, Notes, Loans and Financing Receivable [Line Items]
Bad debt expense	$ 1.1	$ 0.9	$ 0.7