Net (Loss) Income Per Share - Schedule of Calculation of Basic and Diluted Net (Loss) Income Per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Numerator:
Net (loss) income	$ (22.4)	$ 4.5	$ (6.6)	$ 29.1	$ (17.9)	$ 22.5
Denominator – Weighted-average common shares outstanding (in thousands):
Basic	15,835,000		15,781,000		15,820,000	15,809,000
Add: dilutive effect of non-vested common shares, restricted stock units and performance shares						120,000
Diluted	15,835,000		15,781,000		15,820,000	15,929,000
Net (loss) income per common share, Basic:	$ (1.42)		$ (0.41)		$ (1.13)	$ 1.42
Net (loss) income per common share, Diluted:	$ (1.42)		$ (0.41)		$ (1.13)	$ 1.41