Retirement Plans (Schedule Of Net Periodic Benefit Cost (Credit) For Pension And Postretirement Plans) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 13	$ 46	$ 25	$ 92
Interest cost	1,892	2,087	3,783	4,173
Expected return on plan assets	(2,827)	(3,111)	(5,654)	(6,221)
Amortization of net actuarial (gain) loss	2,345	1,305	4,691	2,611
Net periodic benefit cost (credit)	1,423	327	2,845	655
Supplemental Retirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	115	140	230	279
Amortization of prior service cost (credit)	31	31	62	62
Amortization of net actuarial (gain) loss	(28)	(4)	(57)	(8)
Net periodic benefit cost (credit)	118	167	235	333
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	9	8	18	16
Interest cost	12	14	23	27
Amortization of prior service cost (credit)	(61)	(61)	(122)	(122)
Amortization of net actuarial (gain) loss	(22)	(31)	(43)	(63)
Net periodic benefit cost (credit)	$ (62)	$ (70)	$ (124)	$ (142)