Income Tax Provision - Schedule of Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Deferred tax provision
Deferred tax provision			$ (18.5)	$ (6.7)
Expense (benefit) from income taxes	$ (12.9)	$ (1.4)	$ (13.3)	$ (4.7)
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Current tax provision
Federal					$ 0.0	$ 0.0
State					0.5	0.1
Foreign					0.2	0.0
Current tax provision					0.7	0.1
Deferred tax provision
Federal					(5.0)	(2.0)
State					(2.2)	(1.0)
Deferred tax provision					(7.2)	(3.0)
Expense (benefit) from income taxes					$ (6.5)	$ (2.9)