Stock-Based Compensation Plans (Schedule Of Stock Based Compensation Expense) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	May 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 24.8	$ 6.2	$ 7.6
Equity Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		33.7	0.0	0.0
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ (3.0)	(1.1)	4.2	4.6
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ (8.5)	$ (7.8)	$ 2.0	$ 3.0