Segment Information - Reconciliation of Comprehensive Income to Adjusted EBITDA by Segment (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2024	Mar. 31, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Net income attributable to Churchill Downs Incorporated			$ 426.8	$ 417.3	$ 439.4
Net income attributable to noncontrolling interest			2.3	0.0	0.0
Net income			429.1	417.3	439.4
Depreciation and amortization			199.1	169.0	113.7
Interest expense			289.8	268.4	147.3
Income tax provision (benefit)			144.1	144.5	169.4
Stock-based compensation expense			36.1	32.9	31.8
Legal reserves			0.0	(1.2)	3.8
Pre-opening expenses			29.6	18.6	13.2
Arlington exit costs			0.0	9.4	5.7
Other expense, net			4.2	7.0	1.7
Transaction (benefit) expense, net			(12.1)	4.8	42.1
Asset impairments			3.9	24.6	38.3
Interest, depreciation and amortization expense related to equity investments			42.0	40.2	42.8
Changes in fair value of Rivers Des Plaines' interest rate swaps			0.0	0.0	(12.6)
Other charges and recoveries, net			(6.9)	2.4	1.0
Gain on sale of assets			0.0	(114.0)	(274.6)
Total adjustments to EBITDA			730.1	606.6	324.2
Adjusted EBITDA			1,159.2	1,023.9	763.6
Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA			1,247.1	1,096.1	823.5
All Other
Segment Reporting Information [Line Items]
Adjusted EBITDA			(87.9)	(72.2)	(59.9)
Live and Historical
Segment Reporting Information [Line Items]
Asset impairments	$ 3.9
Live and Historical | Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA			574.6	475.4	287.5
Wagering Services and Solutions
Segment Reporting Information [Line Items]
Asset impairments		$ 4.9
Wagering Services and Solutions | Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA			165.6	132.1	114.1
Gaming | Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA			506.9	488.6	421.9
Rivers Des Plaines
Segment Reporting Information [Line Items]
Rivers Des Plaines' legal reserves and transactions costs			$ 0.3	$ 0.0	$ 0.6