Acquisitions - Exacta Systems (Details) - USD ($) $ in Millions		12 Months Ended
	Aug. 22, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Deferred payments for acquisition of business included in other liabilities		$ 4.9	$ 0.0	$ 0.0
Goodwill		899.9	723.8	366.8
Additions		177.1	357.0
Operating Segments | Live and Historical Racing
Business Acquisition [Line Items]
Goodwill		376.2	280.3	52.4
Additions		95.9	227.9
Operating Segments | TwinSpires
Business Acquisition [Line Items]
Goodwill		233.4	152.2	$ 152.2
Additions		81.2	$ 0.0
Exacta Systems
Business Acquisition [Line Items]
Total consideration	$ 248.2
Payments to acquire business	241.3
Deferred payments for acquisition of business included in other liabilities	$ 6.9
Payment term	2 years
Cash acquired in the acquisition	$ 1.8
Property and equipment	9.0
Goodwill	$ 177.1	177.1
Exacta Systems | Operating Segments | Live and Historical Racing
Business Acquisition [Line Items]
Additions		95.9
Exacta Systems | Operating Segments | TwinSpires
Business Acquisition [Line Items]
Additions		$ 81.2