Comprehensive (Loss) Income - Components of Other Comprehensive (Loss) Income and Income Tax Benefit Allocated (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income Loss [Line Items]
Accumulated other comprehensive income (loss) before tax amount	$ (2.4)	$ (0.5)	$ (0.6)
Accumulated other comprehensive income (loss) tax amount	(0.7)	(0.2)
Accumulated other comprehensive income (loss) net of tax amount	(1.7)	(0.3)	(0.6)
Translation Adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Accumulated other comprehensive income (loss) before tax amount	0.1	0.1	(0.6)
Accumulated other comprehensive income (loss) net of tax amount	0.1	0.1	$ (0.6)
Change in Fair Value of Interest Rate Collars
Accumulated Other Comprehensive Income Loss [Line Items]
Accumulated other comprehensive income (loss) before tax amount	(2.5)	(0.6)
Accumulated other comprehensive income (loss) tax amount	(0.7)	(0.2)
Accumulated other comprehensive income (loss) net of tax amount	$ (1.8)	$ (0.4)