Pension and Postretirement Benefits (Components Of Net Periodic Benefits Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 5.5	$ 6.0	$ 6.4
Interest cost	22.4	18.4	26.1
Expected return on plan assets	(56.4)	(54.6)	(57.5)
Amortization of prior service cost	(0.1)	(0.1)	(0.3)
Amortization of net loss (gain)	15.2	23.4	19.1
Recognized curtailment (gain) loss	(1.0)	(1.3)	(2.3)
Settlement loss	12.1	1.4	1.7
Net periodic (benefit) cost	(2.3)	(6.8)	(6.8)
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.2	0.3	0.3
Interest cost	0.7	0.6	0.9
Expected return on plan assets	0.0	0.0	0.0
Amortization of prior service cost	(1.1)	(1.1)	(1.1)
Amortization of net loss (gain)	0.0	0.0	0.0
Recognized curtailment (gain) loss	0.0	0.0	0.0
Settlement loss	0.0	0.0	0.0
Net periodic (benefit) cost	$ (0.2)	$ (0.2)	$ 0.1