Segment Information - Schedule of Total Assets and Capital Expenditures by Operating Segment (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 7,170.1		$ 6,955.5
Capital expenditures:	292.0	$ 312.4
Operating Segments
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	6,464.6		6,267.7
Capital expenditures:	284.0	308.6
Operating Segments | Live and Historical
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	4,040.0		3,872.9
Capital expenditures:	188.3	239.8
Operating Segments | TwinSpires
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	480.2		473.9
Capital expenditures:	7.2	6.4
Operating Segments | Gaming
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	1,944.4		1,920.9
Capital expenditures:	88.5	62.4
All Other
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	705.5		$ 687.8
Capital expenditures:	$ 8.0	$ 3.8