Consolidated Statements of Comprehensive (Loss) Income - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net revenue:
Net revenues	$ 1,054.0	$ 1,329.7	$ 1,009.0
Operating expense:
Selling, general and administrative expense	114.8	122.0	90.6
Impairment of intangible assets	17.5	0.0	0.0
Transaction expense, net	1.0	5.3	10.3
Total operating expense	993.8	1,114.0	820.2
Operating income	60.2	215.7	188.8
Other income (expense):
Interest expense, net	(80.0)	(70.9)	(40.1)
Equity in income of unconsolidated investments	27.7	50.6	29.6
Gain on Ocean Downs/Saratoga transaction	0.0	0.0	54.9
Miscellaneous, net	0.1	1.0	0.7
Total other (expense) income	(52.2)	(19.3)	45.1
Income from continuing operations before provision for income taxes	8.0	196.4	233.9
Income tax benefit (provision)	5.3	(56.8)	(51.3)
Income from continuing operations, net of tax	13.3	139.6	182.6
(Loss) income from discontinued operations, net of tax	(95.4)	(2.4)	170.2
Net (loss) income	(82.1)	137.2	352.8
Net loss attributable to noncontrolling interest	0.2	0.3	0.0
Net (loss) income attributable to Churchill Downs Incorporated	$ (81.9)	$ 137.5	$ 352.8
Net income (loss) per common share data - basic:
Continuing operations (in dollars per share)	$ 0.34	$ 3.49	$ 4.42
Discontinued operations (in dollars per share)	(2.41)	(0.06)	4.12
Net (loss) income per common share - basic (in dollars per share)	(2.07)	3.43	8.54
Net income (loss) per common share data - diluted:
Continuing operations (in dollars per share)	0.33	3.44	4.39
Discontinued operations (in dollars per share)	(2.41)	(0.06)	4.09
Net (loss) income per common share - diluted (in dollars per share)	$ (2.08)	$ 3.38	$ 8.48
Weighted average shares outstanding:
Basic (in shares)	39.6	40.1	41.3
Diluted (in shares)	40.1	40.6	41.6
Other comprehensive income (loss):
Foreign currency translation, net of tax	$ 0.0	$ 0.0	$ 0.6
Change in pension benefits, net of tax	0.0	0.0	(0.2)
Other comprehensive income	0.0	0.0	0.4
Comprehensive (loss) income attributable to Churchill Downs Incorporated	(81.9)	137.5	353.2
Churchill Downs
Net revenue:
Net revenues	142.8	274.2	195.8
Operating expense:
Operating expense	141.9	163.8	116.3
Online Wagering
Net revenue:
Net revenues	408.3	290.5	290.2
Operating expense:
Operating expense	273.3	205.8	196.1
Gaming
Net revenue:
Net revenues	441.4	692.4	449.5
Operating expense:
Operating expense	360.4	528.1	331.0
All Other
Net revenue:
Net revenues	61.5	72.6	73.5
Operating expense:
Operating expense	$ 84.9	$ 89.0	$ 75.9