Investments in and Advances to Unconsolidated Affiliates (Details) $ / shares in Units, $ in Millions					1 Months Ended	3 Months Ended				6 Months Ended
	May 19, 2020 shares	May 19, 2020 shares	May 14, 2020 shares	Feb. 20, 2020 $ / shares shares	Feb. 29, 2020 USD ($) option $ / shares	Jun. 30, 2021 USD ($) $ / shares shares	Mar. 31, 2021 $ / shares shares	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Jun. 30, 2021 USD ($) $ / shares shares	Jun. 30, 2020 USD ($)	Mar. 15, 2021	Dec. 31, 2020 USD ($) $ / shares
Schedule of Equity Method Investments [Line Items]
Common stock, par value (in dollars per share) | $ / shares						$ 0.01				$ 0.01			$ 0.01
Investment purchase price, cash										$ 0.0	$ 135.0
Investment purchase price, equity											23.1
Common stock offerings ( in shares) | shares	2,500,000	19,166,667	16,666,667				151,200
Preferred stock, par value (in dollars per share) | $ / shares							$ 0.01
Return on investment from unconsolidated affiliates										$ 13.4	10.5
Sam Houston Race Park and Valley Race Park | PM Texas Holdings, LLC
Schedule of Equity Method Investments [Line Items]
Business acquisition, percentage of voting interests acquired												50.00%
Series D Preferred Stock
Schedule of Equity Method Investments [Line Items]
Common stock offerings ( in shares) | shares				883			43
Preferred stock, par value (in dollars per share) | $ / shares				$ 0.01		$ 0.01				$ 0.01			$ 0.01
Preferred stock, conversion ratio				0.001
Preferred stock, conversion period				4 years
Preferred stock, percent to convert in each tranche				20.00%
Convertible preferred stock, shares issued upon conversion (in shares) | shares						26				26
Barstool Sports, Inc
Schedule of Equity Method Investments [Line Items]
Ownership interest						36.00%				36.00%
Investment acquired, percent					36.00%
Investment acquired, percent, delayed basis					1.00%					1.00%
Common stock, par value (in dollars per share) | $ / shares					$ 0.0001		$ 0.0001
Investment purchase price					$ 161.2
Investment purchase price, cash					135.0
Investment purchase price, equity					$ 23.1
Investment acquired, period after which ownership will increase					3 years
Investment acquired, ownership percentage following additional investment					50.00%
Investment acquired, expected additional investment					$ 62.0
Investment acquired, valuation of acquiree total common stock outstanding at time of acquisition					$ 450.0
Investment acquired, period after which remaining shares of investment are callable					3 years
Investment acquired, fair market value at time of exercise, cap					$ 650.0
Investment acquired, multiplier of revenue to calculate floor at time of exercise					2.25
Equity method investment, ownership percentage							0.30%
Commercial agreement term					10 years
Commercial agreement number of renewals | option					3
Commercial agreement renewal term					10 years
Commercial agreement term with exercise of renewals					40 years
Customer list intangible asset						$ 1.3				$ 1.3			$ 1.6
Prepaid advertising						16.0				16.0			16.5
Prepaid advertising, long-term						14.9				14.9			15.4
Investment balance						$ 155.7				$ 155.7			147.5
Kansas Entertainment
Schedule of Equity Method Investments [Line Items]
Ownership interest						50.00%				50.00%
Investment balance						$ 86.3				$ 86.3			$ 85.2
Return on investment from unconsolidated affiliates						$ 7.9				$ 13.4	$ 8.7
Freehold Raceway
Schedule of Equity Method Investments [Line Items]
Ownership interest						50.00%				50.00%
MAXXAM
Schedule of Equity Method Investments [Line Items]
Ownership interest						50.00%				50.00%
Other-than-temporary impairment of investment								$ 0.0	$ 4.6	$ 0.0