Segment Information - Schedule of Adjusted EBITDA by Segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 218.2	$ 163.2	$ 804.8	$ 582.9
Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA	237.1	177.2	858.9	624.9
Live and Historical Racing | Operating Segments
Segment Reporting Information [Line Items]
Taxes and purses	(62.0)	(31.6)	(203.9)	(118.0)
Marketing and advertising	(7.6)	(3.6)	(27.9)	(12.9)
Salaries and benefits	(27.9)	(13.3)	(80.0)	(43.1)
Content expense	(1.6)	(0.6)	(5.1)	(2.2)
Selling, general and administrative expense	(7.4)	(3.4)	(23.4)	(9.7)
Other operating expense	(39.0)	(15.6)	(123.6)	(53.6)
Other income	0.9	0.2	1.1	0.3
Adjusted EBITDA	80.9	34.5	386.5	226.3
Net revenue	225.5	102.4	849.3	465.5
TwinSpires | Operating Segments
Segment Reporting Information [Line Items]
Taxes and purses	(5.8)	(6.6)	(17.8)	(21.3)
Marketing and advertising	(1.3)	(1.3)	(8.0)	(11.4)
Salaries and benefits	(7.0)	(6.3)	(20.7)	(19.9)
Content expense	(49.4)	(49.3)	(161.1)	(160.5)
Selling, general and administrative expense	(3.0)	(2.7)	(8.1)	(7.9)
Other operating expense	(12.0)	(10.1)	(36.0)	(37.2)
Other income	0.0	0.0	1.1	0.0
Adjusted EBITDA	33.9	31.1	97.2	89.1
Net revenue	112.4	107.4	347.8	347.3
Gaming | Operating Segments
Segment Reporting Information [Line Items]
Taxes and purses	(81.4)	(70.6)	(246.7)	(206.1)
Marketing and advertising	(8.9)	(4.1)	(26.5)	(11.3)
Salaries and benefits	(35.2)	(24.6)	(109.2)	(72.0)
Content expense	(2.4)	(2.7)	(6.9)	(6.4)
Selling, general and administrative expense	(9.9)	(7.1)	(32.4)	(20.4)
Other operating expense	(32.1)	(21.7)	(92.1)	(63.9)
Other income	47.3	56.5	144.6	140.0
Adjusted EBITDA	122.3	111.6	375.2	309.5
Net revenue	$ 244.9	$ 185.9	$ 744.4	$ 549.6