Segment Information - Schedule of Adjusted EBITDA by Segment (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Segment Reporting Information [Line Items]
Revenues	$ 768.5	$ 582.5	$ 1,328.0	$ 946.6
Adjusted EBITDA	363.7	291.2	586.6	419.7
Live and Historical
Segment Reporting Information [Line Items]
Revenues	408.0	275.9	623.8	363.1
Taxes and purses	(85.4)	(59.6)	(141.9)	(86.4)
Marketing and advertising	(12.1)	(6.4)	(20.3)	(9.3)
Salaries and benefits	(30.3)	(18.9)	(52.1)	(29.8)
Content expense	(2.0)	(1.0)	(3.5)	(1.6)
Selling, general and administrative expense	(7.3)	(3.0)	(16.0)	(6.3)
Other operating expense	(47.6)	(23.2)	(84.6)	(38.0)
Other income	0.2	0.1	0.2	0.1
Adjusted EBITDA	223.5	163.9	305.6	191.8
TwinSpires
Segment Reporting Information [Line Items]
Revenues	139.1	138.5	235.5	239.9
Taxes and purses	(7.0)	(7.2)	(12.0)	(14.7)
Marketing and advertising	(5.3)	(5.0)	(6.7)	(10.1)
Salaries and benefits	(7.5)	(6.9)	(13.7)	(13.6)
Content expense	(68.7)	(68.1)	(111.7)	(111.2)
Selling, general and administrative expense	(2.7)	(2.6)	(5.1)	(5.2)
Other operating expense	(14.0)	(14.8)	(24.0)	(27.1)
Other income	0.0	0.0	1.0	0.0
Adjusted EBITDA	33.9	33.9	63.3	58.0
Gaming
Segment Reporting Information [Line Items]
Revenues	247.9	184.5	499.5	363.7
Taxes and purses	(81.7)	(68.2)	(165.3)	(135.5)
Marketing and advertising	(9.0)	(3.7)	(17.6)	(7.2)
Salaries and benefits	(39.5)	(23.5)	(74.0)	(47.4)
Content expense	(2.7)	(2.2)	(4.5)	(3.7)
Selling, general and administrative expense	(10.3)	(6.7)	(22.5)	(13.3)
Other operating expense	(30.0)	(22.2)	(60.0)	(42.2)
Other income	48.7	48.8	97.3	83.5
Adjusted EBITDA	$ 123.4	$ 106.8	$ 252.9	$ 197.9