Earnings Per Share - Undistributed Net Earnings From Continuing Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Earnings Per Share [Abstract]
Basic earnings (losses) per share numerators	$ 23.3	$ (4.7)	$ 219.6	$ (148.3)
Dividends declared, net of restricted common share amounts	0.0	0.0	(2.5)	(3.0)
Total undistributed net earnings (losses), net of restricted common share amounts	$ 23.3	$ (4.7)	$ 217.1	$ (151.3)