Net Earnings Per Share (Reconciliation of Earnings (loss) to Earnings (loss) Attributable to Common Shares Used in Basic and Diluted (Loss) Earnings Per Share Calculation) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Earnings Per Share [Abstract]
Net earnings	$ 47.3	$ 44.4
(Earnings) allocated to participating vested share awards	0.0	(0.1)
Earnings from continuing operations attributable to common shares	$ 47.3	$ 44.3