Accumulated Other Comprehensive Income (Loss) (Components Of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 381,177	$ 320,054	$ 293,844
Other comprehensive income (loss) before reclassifications	(10,275)	2,028	(1,466)
Amounts reclassified from accumulated other comprehensive income (loss)	910	7	(1,158)
Total other comprehensive income (loss), net of tax	(9,365)	2,035	(2,624)
Balance	396,293	381,177	320,054
Hedging Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	(276)
Total other comprehensive income (loss), net of tax	(276)
Balance	(276)
Securities Available-For-Sale and Transferred Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(3,275)	(3,729)	(696)
Other comprehensive income (loss) before reclassifications	(4,897)	1,131	(1,318)
Amounts reclassified from accumulated other comprehensive income (loss)	403	(677)	(1,715)
Total other comprehensive income (loss), net of tax	(4,494)	454	(3,033)
Balance	(7,769)	(3,275)	(3,729)
Pension And Post-Retirement Obligations [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(8,641)	(10,222)	(10,631)
Other comprehensive income (loss) before reclassifications	(5,102)	897	(148)
Amounts reclassified from accumulated other comprehensive income (loss)	507	684	557
Total other comprehensive income (loss), net of tax	(4,595)	1,581	409
Balance	(13,236)	(8,641)	(10,222)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(11,916)	(13,951)	(11,327)
Total other comprehensive income (loss), net of tax	(9,365)	2,035	(2,624)
Balance	$ (21,281)	$ (11,916)	$ (13,951)