Segment Information Adjusted EBITDA by Segment (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Net revenue	$ 189,300,000	$ 167,500,000
Adjusted EBITDA	49,200,000	36,300,000
Racing Segment [Member]
Segment Reporting Information [Line Items]
Net revenue	26,200,000	26,100,000
Taxes & purses	10,300,000	10,200,000
Marketing & advertising	800,000	700,000
Salaries & benefits	8,600,000	8,600,000
Content expense	3,100,000	3,200,000
SG&A expense	4,000,000	3,800,000
Other operating expense	8,800,000	9,300,000
Other income	0	0
Adjusted EBITDA	(9,400,000)	(9,700,000)
Casino Segment [Member]
Segment Reporting Information [Line Items]
Net revenue	98,100,000	87,500,000
Taxes & purses	32,400,000	29,100,000
Marketing & advertising	3,200,000	3,000,000
Salaries & benefits	13,500,000	13,100,000
Content expense	0	0
SG&A expense	5,400,000	5,200,000
Other operating expense	10,100,000	11,400,000
Other income	10,800,000	9,600,000
Adjusted EBITDA	44,300,000	35,300,000
TwinSpires [Member]
Segment Reporting Information [Line Items]
Net revenue	63,600,000	52,300,000
Taxes & purses	3,400,000	3,000,000
Marketing & advertising	800,000	1,000,000
Salaries & benefits	2,100,000	2,200,000
Content expense	32,200,000	25,400,000
SG&A expense	2,800,000	2,700,000
Other operating expense	5,800,000	4,800,000
Other income	0	0
Adjusted EBITDA	16,500,000	13,200,000
Other Segments [Member]
Segment Reporting Information [Line Items]
Net revenue	5,500,000	5,500,000
Taxes & purses	0	0
Marketing & advertising	0	0
Salaries & benefits	3,200,000	2,900,000
Content expense	0	0
SG&A expense	700,000	800,000
Other operating expense	1,300,000	1,300,000
Other income	0	100,000
Adjusted EBITDA	300,000	600,000
Corporate
Segment Reporting Information [Line Items]
Net revenue	0	0
Taxes & purses	0	0
Marketing & advertising	0	0
Salaries & benefits	0	0
Content expense	0	0
SG&A expense	2,400,000	2,900,000
Other operating expense	200,000	200,000
Other income	100,000	0
Adjusted EBITDA	(2,500,000)	(3,100,000)
Saratoga Harness Racing Inc Joint Venture [Member] | Racing Segment [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	(9,400,000.0)	(9,700,000.0)
Saratoga Harness Racing Inc Joint Venture [Member] | Casino Segment [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	44,300,000.0	35,300,000.0
Saratoga Harness Racing Inc Joint Venture [Member] | TwinSpires [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	16,500,000.0	13,200,000.0
Saratoga Harness Racing Inc Joint Venture [Member] | Other Investments Segment [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 300,000.0	$ 600,000.0