Other Balance Sheet Items - Schedule of Accounts Receivable (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Accounts Receivable, Net, Current [Abstract]
Accounts receivable, gross	$ 41.4	$ 41.7
Allowance for doubtful accounts	(4.9)	(4.4)
Accounts receivable, net	36.5	37.3
Trade receivables
Accounts Receivable, Net, Current [Abstract]
Accounts receivable, gross	6.5	12.3
Simulcast and online wagering receivables
Accounts Receivable, Net, Current [Abstract]
Accounts receivable, gross	26.7	20.9
Other receivables
Accounts Receivable, Net, Current [Abstract]
Accounts receivable, gross	$ 8.2	$ 8.5