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						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Numerator:
Net (loss) income	$ (2.3)	$ (22.4)	$ 4.5	$ 0.4	$ (6.6)	$ 29.1	$ (20.2)	$ 22.9
Denominator – Weighted-average common shares outstanding (in thousands):
Basic	15,852,000			15,794,000			15,831,000	15,804,000
Add: dilutive effect of non-vested common shares, restricted stock units and performance shares				71,000				100,000
Diluted	15,852,000			15,865,000			15,831,000	15,904,000
Net (loss) income per common share, Basic:	$ (0.14)			$ 0.02			$ (1.28)	$ 1.45
Net (loss) income per common share, Diluted:	$ (0.14)			$ 0.02			$ (1.28)	$ 1.44