Segment Information - Schedule of Adjusted EBITDA by Segment (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 444.8	$ 363.7	$ 687.3	$ 586.6
Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA	466.1	380.8	729.3	621.8
Live and Historical | Operating Segments
Segment Reporting Information [Line Items]
Revenues	490.2	408.0	739.1	623.8
Gaming taxes and purses	(100.0)	(85.4)	(165.0)	(141.9)
Marketing and advertising	(12.5)	(12.1)	(21.8)	(20.3)
Salaries and benefits	(36.5)	(30.3)	(63.3)	(52.1)
Content expense	(2.1)	(2.0)	(3.4)	(3.5)
Selling, general and administrative expense	(8.5)	(7.3)	(17.3)	(16.0)
Maintenance, insurance and utilities	(11.5)	(10.1)	(21.8)	(19.4)
Property and other taxes	(1.8)	(1.5)	(4.5)	(2.7)
Other operating expense	(38.3)	(36.0)	(62.2)	(62.5)
Other income	0.2	0.2	0.2	0.2
Adjusted EBITDA	279.2	223.5	380.0	305.6
TwinSpires | Operating Segments
Segment Reporting Information [Line Items]
Revenues	159.9	139.1	274.0	235.5
Gaming taxes and purses	(7.3)	(7.0)	(12.2)	(12.0)
Marketing and advertising	(4.9)	(5.3)	(6.1)	(6.7)
Salaries and benefits	(8.0)	(7.5)	(15.9)	(13.7)
Content expense	(73.3)	(68.7)	(117.3)	(111.7)
Selling, general and administrative expense	(4.3)	(2.7)	(8.8)	(5.1)
Maintenance, insurance and utilities	(1.0)	(0.8)	(2.0)	(1.7)
Property and other taxes	0.0	(0.1)	(0.1)	(0.1)
Other operating expense	(14.9)	(13.1)	(25.8)	(22.2)
Other income	0.0	0.0	0.0	1.0
Adjusted EBITDA	46.2	33.9	85.8	63.3
Gaming | Operating Segments
Segment Reporting Information [Line Items]
Revenues	274.4	247.9	517.6	499.5
Gaming taxes and purses	(83.5)	(81.7)	(164.0)	(165.3)
Marketing and advertising	(9.2)	(9.0)	(17.0)	(17.6)
Salaries and benefits	(40.3)	(39.5)	(78.3)	(74.0)
Content expense	(2.6)	(2.7)	(4.4)	(4.5)
Selling, general and administrative expense	(11.8)	(10.3)	(22.0)	(22.5)
Maintenance, insurance and utilities	(11.1)	(9.6)	(20.7)	(19.4)
Property and other taxes	(3.3)	(3.0)	(6.7)	(6.3)
Other operating expense	(20.2)	(17.4)	(38.5)	(34.3)
Other income	48.3	48.7	97.5	97.3
Adjusted EBITDA	$ 140.7	$ 123.4	$ 263.5	$ 252.9