Comprehensive (Loss) Income - Components of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
AOCI Attributable to Parent, Net of Tax
Beginning Balance	$ 374.1
Other comprehensive (loss) income before reclassification	(2.8)	$ (0.3)	$ (0.6)
Amounts reclassified from accumulated other comprehensive loss	1.1
Ending Balance	183.1	374.1
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax
Beginning Balance	(2.3)	(2.4)	(1.2)
Other comprehensive (loss) income before reclassification	0.1	0.1	(0.6)
Ending Balance	(2.2)	(2.3)	(2.4)
Foreign Currency Translation Adjustments | Cumulative Effect, Period of Adoption, Adjustment
AOCI Attributable to Parent, Net of Tax
Beginning Balance		(0.6)
Ending Balance			$ (0.6)
Accounting Standards Update Extensible List			us-gaap:AccountingStandardsUpdate201802Member
Change in Fair Value of Interest Rate Collars
AOCI Attributable to Parent, Net of Tax
Beginning Balance	(0.4)
Other comprehensive (loss) income before reclassification	(2.9)	(0.4)
Amounts reclassified from accumulated other comprehensive loss	1.1
Ending Balance	(2.2)	(0.4)
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax
Beginning Balance	(2.7)	(2.4)	$ (1.2)
Ending Balance	$ (4.4)	(2.7)	(2.4)
Accumulated Other Comprehensive Loss | Cumulative Effect, Period of Adoption, Adjustment
AOCI Attributable to Parent, Net of Tax
Beginning Balance		$ (0.6)
Ending Balance			$ (0.6)
Accounting Standards Update Extensible List			us-gaap:AccountingStandardsUpdate201802Member