Pension And Postretirement Benefits (Schedule Of Information For Pension Plans With An Accumulated Benefit Obligation In Excess Of Plan Assets) (Details) - Pension Benefits [Member] - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 860.0	$ 834.8
Accumulated benefit obligation	852.2	827.8
Fair value of plan assets	$ 627.3	$ 593.3