Earnings Per Common Share - Summary of Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Earnings per common share—basic
Net income	$ 29.7	$ 38.5	$ 172.1	$ 230.6
Weighted-average common shares outstanding—basic (in shares)	185.2	184.8	185.2	184.9
Earnings (loss) per common share (in dollars per share)	$ 0.16	$ 0.21	$ 0.93	$ 1.25
Earnings per common share—diluted
Net income	$ 29.7	$ 38.5	$ 172.1	$ 230.6
Interest expense attributable to convertible notes	1.6	1.6	4.8	4.8
Net income attributable to earnings per common share—diluted	$ 31.3	$ 40.1	$ 176.9	$ 235.4
Weighted-average common shares outstanding—basic (in shares)	185.2	184.8	185.2	184.9
Convertible notes weighted-average shares outstanding (in shares)	14.7	14.7	14.7	14.7
Outstanding options, restricted stock units and performance share units (in shares)	1.3	2.3	1.4	1.4
Weighted-average common shares outstanding—diluted (in shares)	201.2	201.8	201.3	201.0
Earnings (loss) per common share—diluted (in dollars per share)	$ 0.16	$ 0.20	$ 0.88	$ 1.17