Earnings (Loss) per Common Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Earnings (Loss) per Common Share
Net income	$ 9.6	$ 0.1
Basic weighted-average shares	82,031,043	81,037,633
Effect of dilutive securities:
Restricted stock awards	3,598,940	499,180
Diluted weighted-average shares	85,629,983	81,536,813
Basic earnings per share (in dollars per share)	$ 0.12	$ 0.00
Diluted earnings per share (in dollars per share)	$ 0.11	$ 0.00