Revenue from Contracts with Customers - Net Revenue From External Customers and Intercompany Revenue From Each Operating Segment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Disaggregation of Revenue [Line Items]
Net revenue	$ 642.6	$ 590.9
Disclosure of complimentary revenue	14.4	13.4
Related Party
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0
Gaming
Disaggregation of Revenue [Line Items]
Net revenue	263.2	239.2
Other
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0
External Customer
Disaggregation of Revenue [Line Items]
Net revenue	642.6	590.9
External Customer | Pari-mutuel, live and simulcast racing
Disaggregation of Revenue [Line Items]
Net revenue	102.0	101.4
External Customer | Pari-mutuel, historical racing
Disaggregation of Revenue [Line Items]
Net revenue	246.1	220.9
External Customer | Racing event-related services
Disaggregation of Revenue [Line Items]
Net revenue	2.1	3.3
External Customer | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	220.9	201.9
External Customer | Other
Disaggregation of Revenue [Line Items]
Net revenue	71.5	63.4
Operating Segments | External Customer
Disaggregation of Revenue [Line Items]
Net revenue	642.6	590.9
Operating Segments | External Customer | Pari-mutuel, live and simulcast racing
Disaggregation of Revenue [Line Items]
Net revenue	102.0	101.4
Operating Segments | External Customer | Pari-mutuel, historical racing
Disaggregation of Revenue [Line Items]
Net revenue	246.1	220.9
Operating Segments | External Customer | Racing event-related services
Disaggregation of Revenue [Line Items]
Net revenue	2.1	3.3
Operating Segments | External Customer | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	220.9	201.9
Operating Segments | External Customer | Other
Disaggregation of Revenue [Line Items]
Net revenue	71.5	63.4
Operating Segments | Live and Historical
Disaggregation of Revenue [Line Items]
Net revenue	272.5	245.1
Operating Segments | Live and Historical | Related Party
Disaggregation of Revenue [Line Items]
Net revenue	3.9	3.8
Operating Segments | Live and Historical | External Customer
Disaggregation of Revenue [Line Items]
Net revenue	272.5	245.1
Operating Segments | Live and Historical | External Customer | Pari-mutuel, live and simulcast racing
Disaggregation of Revenue [Line Items]
Net revenue	11.2	11.0
Operating Segments | Live and Historical | External Customer | Pari-mutuel, historical racing
Disaggregation of Revenue [Line Items]
Net revenue	236.4	212.1
Operating Segments | Live and Historical | External Customer | Racing event-related services
Disaggregation of Revenue [Line Items]
Net revenue	1.4	1.1
Operating Segments | Live and Historical | External Customer | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	3.3	3.1
Operating Segments | Live and Historical | External Customer | Other
Disaggregation of Revenue [Line Items]
Net revenue	20.2	17.8
Operating Segments | Wagering Services and Solutions
Disaggregation of Revenue [Line Items]
Net revenue	106.9	106.6
Operating Segments | Wagering Services and Solutions | Related Party
Disaggregation of Revenue [Line Items]
Net revenue	8.9	7.5
Operating Segments | Wagering Services and Solutions | External Customer
Disaggregation of Revenue [Line Items]
Net revenue	106.9	106.6
Operating Segments | Wagering Services and Solutions | External Customer | Pari-mutuel, live and simulcast racing
Disaggregation of Revenue [Line Items]
Net revenue	80.1	79.8
Operating Segments | Wagering Services and Solutions | External Customer | Pari-mutuel, historical racing
Disaggregation of Revenue [Line Items]
Net revenue	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
Operating Segments | Wagering Services and Solutions | External Customer | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	3.9	5.7
Operating Segments | Wagering Services and Solutions | External Customer | Other
Disaggregation of Revenue [Line Items]
Net revenue	22.9	21.1
Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	263.2	239.2
Operating Segments | Gaming | Related Party
Disaggregation of Revenue [Line Items]
Net revenue	4.0	4.0
Operating Segments | Gaming | External Customer
Disaggregation of Revenue [Line Items]
Net revenue	263.2	239.2
Operating Segments | Gaming | External Customer | Pari-mutuel, live and simulcast racing
Disaggregation of Revenue [Line Items]
Net revenue	10.7	10.6
Operating Segments | Gaming | External Customer | Pari-mutuel, historical racing
Disaggregation of Revenue [Line Items]
Net revenue	9.7	8.8
Operating Segments | Gaming | External Customer | Racing event-related services
Disaggregation of Revenue [Line Items]
Net revenue	0.7	2.2
Operating Segments | Gaming | External Customer | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	213.7	193.1
Operating Segments | Gaming | External Customer | Other
Disaggregation of Revenue [Line Items]
Net revenue	28.4	24.5
All Other
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0
All Other | Related Party
Disaggregation of Revenue [Line Items]
Net revenue	2.0	0.0
All Other | External Customer
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0
All Other | External Customer | Pari-mutuel, live and simulcast racing
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0
All Other | External Customer | Pari-mutuel, historical racing
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0
All Other | External Customer | Racing event-related services
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0
All Other | External Customer | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0
All Other | External Customer | Other
Disaggregation of Revenue [Line Items]
Net revenue	0.0	0.0
Eliminations | Related Party
Disaggregation of Revenue [Line Items]
Net revenue	(18.8)	(15.3)
Churchill Downs Racetrack | Operating Segments | Live and Historical
Disaggregation of Revenue [Line Items]
Net revenue	3.6	3.1
Louisville | Operating Segments | Live and Historical
Disaggregation of Revenue [Line Items]
Net revenue	52.2	53.7
Northern Kentucky | Operating Segments | Live and Historical
Disaggregation of Revenue [Line Items]
Net revenue	31.2	28.5
Southwestern Kentucky | Operating Segments | Live and Historical
Disaggregation of Revenue [Line Items]
Net revenue	40.5	38.6
Western Kentucky | Operating Segments | Live and Historical
Disaggregation of Revenue [Line Items]
Net revenue	12.4	6.8
Virginia | Operating Segments | Live and Historical
Disaggregation of Revenue [Line Items]
Net revenue	129.3	111.2
New Hampshire | Operating Segments | Live and Historical
Disaggregation of Revenue [Line Items]
Net revenue	3.3	3.2
Florida | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	25.3	26.1
Iowa | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	23.5	23.4
Indiana | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	31.6	0.0
Louisiana | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	44.6	44.3
Maine | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	25.0	26.8
Maryland | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	20.8	21.6
Mississippi | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	25.1	26.0
New York | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	43.4	45.0
Pennsylvania | Operating Segments | Gaming
Disaggregation of Revenue [Line Items]
Net revenue	$ 23.9	$ 26.0