Earnings per Common Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Earnings per Common Share
Net loss, basic	$ (10.8)	$ (101.7)	$ (25.8)	$ (139.7)
Basic weighted-average shares	81,938,341	81,502,527	81,644,131	82,262,724
Diluted weighted-average shares	81,938,341	81,502,527	81,644,131	82,262,724
Basic and diluted (loss) earnings per common share
Basic (in dollars per share)	$ (0.13)	$ (1.25)	$ (0.32)	$ (1.70)
Diluted (in dollars per share)	$ (0.13)	$ (1.25)	$ (0.32)	$ (1.70)