Retirement Plans (Schedule Of Net Periodic Benefit Cost (Credit) For Pension And Postretirement Plans) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 0
Interest cost	1,762	1,783
Expected return on plan assets	(2,754)	(3,090)
Amortization of net actuarial (gain) loss	1,659	1,574
Net periodic benefit cost (credit)	667	267
Supplemental Retirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	100	101
Amortization of prior service cost (credit)	0	0
Amortization of net actuarial (gain) loss	31	31
Net periodic benefit cost (credit)	131	132
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	5	8
Interest cost	10	10
Amortization of prior service cost (credit)	0	0
Amortization of net actuarial (gain) loss	(17)	(13)
Net periodic benefit cost (credit)	$ (2)	$ 5