Employee Benefit Plans (Schedule Of Amounts Not Yet Reflected In Net Periodic Benefit Cost And Included In Accumulated Other Comprehensive Income (Loss), Pre-Tax Basis) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Prior service credit (cost)	$ 1,806	$ 2,077
Accumulated loss	(33,499)	(33,285)
Accumulated other comprehensive loss	(31,693)	(31,208)
Cumulative employer contributions in excess of net periodic benefit cost	19,286	14,050
Net amount recognized as an accrued benefit liability on the December 31 balance sheet	(12,407)	(17,158)
Net loss arising during period	(2,527)	(248)
Amortization or settlement recognition of net loss	2,313	2,565
Amortization of Prior Service Cost (Credit)	(271)	(271)	$ (271)
Total recognized in other comprehensive income	(485)	2,046
Total expense recognized in net periodic pension cost and other comprehensive income	$ (1,189)	$ 1,059