Share-Based Compensation Plans (Schedule of Compensation Cost and Income Tax Benefit) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-Based Payment Arrangement [Abstract]
Compensation cost for stock-based compensation	$ 0.5	$ 13.1	$ 13.4	$ 24.9
Total income tax (cost)/ benefit recognized for share-based arrangements		$ 0.7	$ (0.2)	$ 1.9