Retirement Plans And Other Postretirement Benefits (Schedule Of Amounts Recognized Before Related Deferred Income Taxes In Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Prior service cost (benefit)	$ 0	$ 5	$ 10
Net actuarial (gain) loss	132,751	144,377	145,782
Other Post-Retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Prior service cost (benefit)	0	0	0
Net actuarial (gain) loss	$ (1,821)	$ (1,238)	$ (1,756)