Revenue from Contracts with Customers - Net Revenue From External Customers and Intercompany Revenue From Each Operating Segment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Net revenue	$ 2,734.3	$ 2,461.7	$ 1,809.8
Other revenue	56.0	50.9	33.9
Related Party
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0	0.0
Gaming
Disaggregation of Revenue [Line Items]
Net revenue	1,039.1	968.6	755.9
Other
Disaggregation of Revenue [Line Items]
Net revenue	0.1	0.9	2.9
External Customer
Disaggregation of Revenue [Line Items]
Net revenue	2,734.3	2,461.7	1,809.8
External Customer | Live and simulcast racing
Disaggregation of Revenue [Line Items]
Net revenue	469.9	468.2	462.3
External Customer | Historical racing
Disaggregation of Revenue [Line Items]
Net revenue	891.9	767.7	383.9
External Customer | Racing event-related services
Disaggregation of Revenue [Line Items]
Net revenue	194.6	152.3	131.6
External Customer | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	885.9	832.2	679.1
External Customer | Other
Disaggregation of Revenue [Line Items]
Net revenue	292.0	241.3	152.9
Operating Segments | External Customer
Disaggregation of Revenue [Line Items]
Net revenue	2,734.2	2,460.8	1,806.9
Operating Segments | External Customer | Live and simulcast racing
Disaggregation of Revenue [Line Items]
Net revenue	469.9	468.2	462.3
Operating Segments | External Customer | Historical racing
Disaggregation of Revenue [Line Items]
Net revenue	891.9	767.7	383.9
Operating Segments | External Customer | Racing event-related services
Disaggregation of Revenue [Line Items]
Net revenue	194.6	152.3	131.6
Operating Segments | External Customer | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	885.9	832.2	679.1
Operating Segments | External Customer | Other
Disaggregation of Revenue [Line Items]
Net revenue	291.9	240.4	150.0
Operating Segments | Live and Historical Racing
Disaggregation of Revenue [Line Items]
Net revenue	1,225.6	1,047.3	614.6
Operating Segments | Live and Historical Racing | Related Party
Disaggregation of Revenue [Line Items]
Net revenue	41.4	37.3	31.8
Operating Segments | Live and Historical Racing | External Customer
Disaggregation of Revenue [Line Items]
Net revenue	1,225.6	1,047.3	614.6
Operating Segments | Live and Historical Racing | External Customer | Live and simulcast racing
Disaggregation of Revenue [Line Items]
Net revenue	91.3	81.9	66.8
Operating Segments | Live and Historical Racing | External Customer | Historical racing
Disaggregation of Revenue [Line Items]
Net revenue	854.9	739.1	374.1
Operating Segments | Live and Historical Racing | External Customer | Racing event-related services
Disaggregation of Revenue [Line Items]
Net revenue	188.0	145.9	129.8
Operating Segments | Live and Historical Racing | External Customer | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	12.6	11.4	3.5
Operating Segments | Live and Historical Racing | External Customer | Other
Disaggregation of Revenue [Line Items]
Net revenue	78.8	69.0	40.4
Operating Segments | Wagering Services and Solutions
Disaggregation of Revenue [Line Items]
Net revenue	469.5	444.9	436.4
Operating Segments | Wagering Services and Solutions | Related Party
Disaggregation of Revenue [Line Items]
Net revenue	31.2	13.5	5.2
Operating Segments | Wagering Services and Solutions | External Customer
Disaggregation of Revenue [Line Items]
Net revenue	469.5	444.9	436.4
Operating Segments | Wagering Services and Solutions | External Customer | Live and simulcast racing
Disaggregation of Revenue [Line Items]
Net revenue	352.2	359.7	367.4
Operating Segments | Wagering Services and Solutions | External Customer | Historical racing
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0	0.0
Operating Segments | Wagering Services and Solutions | External Customer | Racing event-related services
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0	0.0
Operating Segments | Wagering Services and Solutions | External Customer | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	17.3	17.3	28.2
Operating Segments | Wagering Services and Solutions | External Customer | Other
Disaggregation of Revenue [Line Items]
Net revenue	100.0	67.9	40.8
Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	1,039.1	968.6	755.9
Operating Segments | Gaming | Related Party
Disaggregation of Revenue [Line Items]
Net revenue	6.3	6.0	5.9
Operating Segments | Gaming | External Customer
Disaggregation of Revenue [Line Items]
Net revenue	1,039.1	968.6	755.9
Operating Segments | Gaming | External Customer | Live and simulcast racing
Disaggregation of Revenue [Line Items]
Net revenue	26.4	26.6	28.1
Operating Segments | Gaming | External Customer | Historical racing
Disaggregation of Revenue [Line Items]
Net revenue	37.0	28.6	9.8
Operating Segments | Gaming | External Customer | Racing event-related services
Disaggregation of Revenue [Line Items]
Net revenue	6.6	6.4	1.8
Operating Segments | Gaming | External Customer | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	856.0	803.5	647.4
Operating Segments | Gaming | External Customer | Other
Disaggregation of Revenue [Line Items]
Net revenue	113.1	103.5	68.8
All Other
Disaggregation of Revenue [Line Items]
Net revenue	0.1	0.9	2.9
All Other | Related Party
Disaggregation of Revenue [Line Items]
Net revenue	6.5	0.0	0.4
All Other | External Customer
Disaggregation of Revenue [Line Items]
Net revenue	0.1	0.9	2.9
All Other | External Customer | Live and simulcast racing
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0	0.0
All Other | External Customer | Historical racing
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0	0.0
All Other | External Customer | Racing event-related services
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0	0.0
All Other | External Customer | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0	0.0
All Other | External Customer | Other
Disaggregation of Revenue [Line Items]
Net revenue	0.1	0.9	2.9
Eliminations | Related Party
Disaggregation of Revenue [Line Items]
Net revenue	(85.4)	(56.8)	(43.3)
Churchill Downs Racetrack | Operating Segments | Live and Historical Racing
Disaggregation of Revenue [Line Items]
Net revenue	259.5	205.8	196.8
Louisville | Operating Segments | Live and Historical Racing
Disaggregation of Revenue [Line Items]
Net revenue	209.1	189.0	169.9
Northern Kentucky | Operating Segments | Live and Historical Racing
Disaggregation of Revenue [Line Items]
Net revenue	98.9	85.8	46.1
Southwestern Kentucky | Operating Segments | Live and Historical Racing
Disaggregation of Revenue [Line Items]
Net revenue	158.3	147.8	131.4
Western Kentucky | Operating Segments | Live and Historical Racing
Disaggregation of Revenue [Line Items]
Net revenue	28.8	31.8	4.5
Virginia | Operating Segments | Live and Historical Racing
Disaggregation of Revenue [Line Items]
Net revenue	458.2	375.4	62.4
New Hampshire | Operating Segments | Live and Historical Racing
Disaggregation of Revenue [Line Items]
Net revenue	12.8	11.7	3.5
Florida | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	100.2	100.7	106.2
Iowa | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	93.3	96.0	15.6
Indiana | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	96.6	0.0	0.0
Louisiana | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	150.2	145.6	140.8
Maine | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	106.0	114.1	114.4
Maryland | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	101.8	106.9	105.3
Mississippi | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	98.7	100.9	101.8
New York | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	183.0	180.5	30.9
Pennsylvania | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	$ 109.3	$ 123.9	$ 140.9