Segment Information - Reconciliation of Comprehensive Income to Adjusted EBITDA by Segment (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Segment Reporting Information [Line Items]
Net income attributable to Churchill Downs Incorporated	$ 209.3	$ 80.4	$ 143.0	$ 155.7	$ 289.7	$ 298.7
Net income attributable to noncontrolling interest	0.9		0.0		0.9	0.0
Net income and comprehensive income	210.2		143.0		290.6	298.7
Depreciation and amortization	49.2		41.8		96.1	79.7
Interest expense	73.5		65.2		143.9	129.9
Income tax provision	84.1		56.2		105.5	109.4
EBITDA	417.0		306.2		636.1	617.7
Stock-based compensation expense	8.9		8.1		16.1	16.7
Pre-opening expense	7.5		3.2		15.8	6.4
Arlington exit costs	0.0		5.9		0.0	9.3
Other expenses, net	0.1		6.6		0.3	6.9
Asset impairments	0.0		24.5		0.0	24.5
Transaction expense, net	0.6		0.5		4.7	0.3
Interest, depreciation and amortization expense related to equity investments	10.5		9.9		20.8	19.7
Other charges and recoveries, net	(0.1)		(1.2)		(6.8)	(0.9)
Gain on sale of Arlington	0.0		0.0		0.0	(114.0)
Total adjustments to EBITDA	27.8		57.5		51.2	(31.1)
Adjusted EBITDA	444.8		363.7		687.3	586.6
Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA	466.1		380.8		729.3	621.8
All Other
Segment Reporting Information [Line Items]
Adjusted EBITDA	(21.3)		(17.1)		(42.0)	(35.2)
Live and Historical | Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA	279.2		223.5		380.0	305.6
TwinSpires | Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA	46.2		33.9		85.8	63.3
Gaming | Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA	140.7		123.4		263.5	252.9
Rivers Des Plaines
Segment Reporting Information [Line Items]
Rivers Des Plaines' legal reserves and transaction costs	$ 0.3		$ 0.0		$ 0.3	$ 0.0