Consolidated Statements Of Comprehensive Income - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net revenue:
Racing	$ 251.1	$ 248.0	$ 261.4
Casinos	332.8	332.9	328.3
TwinSpires	220.6	200.2	191.0
Big Fish Games	486.2	413.7	13.9
Other Investments	16.9	16.6	16.5
Corporate	1.0	0.9	1.1
Total net revenue	1,308.6	1,212.3	812.2
Operating expense:
Racing	187.7	189.9	216.3
Casinos	241.3	241.1	243.3
TwinSpires	146.7	135.4	138.2
Big Fish Games	398.9	340.1	16.0
Other Investments	16.5	16.3	17.6
Corporate	1.9	0.1	1.9
Selling, general and administrative expense	100.2	90.8	76.0
Research and development	39.0	39.4	0.0
Gain on Calder land sale	(23.7)	0.0	0.0
Calder exit costs	2.5	13.9	2.3
Acquisition expenses, net	3.4	21.7	10.2
Total operating expense	1,114.4	1,088.7	721.8
Operating income	194.2	123.6	90.4
Other income (expense):
Interest expense	(43.7)	(28.6)	(20.8)
Equity in income of unconsolidated investments	17.4	11.2	6.3
Miscellaneous, net	0.2	5.9	0.6
Total other expense	(26.1)	(11.5)	(13.9)
Income from operations before provision for income taxes	168.1	112.1	76.5
Income tax provision	(60.0)	(46.9)	(30.1)
Net income	$ 108.1	$ 65.2	$ 46.4
Net income per common share data:
Basic net income (in dollars per share)	$ 6.52	$ 3.75	$ 2.67
Diluted net income (in dollars per share)	$ 6.42	$ 3.71	$ 2.64
Weighted average shares outstanding:
Basic (in shares)	16.4	17.2	17.3
Diluted (in shares)	16.8	17.6	17.6
Other comprehensive loss:
Foreign currency translation, net of tax	$ 0.2	$ (0.5)	$ (0.1)
Change in pension benefits, net of tax	(0.8)	0.0	0.0
Other comprehensive loss	(0.6)	(0.5)	(0.1)
Comprehensive income	$ 107.5	$ 64.7	$ 46.3