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Accumulated Other Comprehensive Income (Loss) (Components Of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands		3 Months Ended				6 Months Ended
	Jan. 01, 2019	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 396,293	$ 408,253	$ 396,293	$ 380,302	$ 381,177	$ 396,293	$ 381,177
Other comprehensive income (loss) before reclassifications		5,164		(2,327)		10,283	(8,762)
Reclassification from AOCI to retained earnings	2,800
Amounts reclassified from accumulated other comprehensive income (loss)		230		194		621	382
Total other comprehensive income (loss), net of tax		5,394	5,510	(2,133)	(6,247)	10,904	(8,380)
Balance		422,354	408,253	386,937	380,302	422,354	386,937
Hedging Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(276)	(530)	(276)	(104)		(276)
Other comprehensive income (loss) before reclassifications		(106)		227		(360)	123
Total other comprehensive income (loss), net of tax		(106)		227		(360)	123
Balance		(636)	(530)	123	(104)	(636)	123
Securities Available-For-Sale and Transferred Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(7,769)	(2,947)	(7,769)	(9,545)	(3,275)	(7,769)	(3,275)
Other comprehensive income (loss) before reclassifications		5,270		(2,554)		10,643	(8,885)
Reclassification from AOCI to retained earnings						(681)
Amounts reclassified from accumulated other comprehensive income (loss)		(31)		67		99	128
Total other comprehensive income (loss), net of tax		5,239		(2,487)		10,742	(8,757)
Balance		2,292	(2,947)	(12,032)	(9,545)	2,292	(12,032)
Pension And Post-Retirement Obligations [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(13,236)	(15,077)	(13,236)	(8,514)	(8,641)	(13,236)	(8,641)
Reclassification from AOCI to retained earnings						(2,102)
Amounts reclassified from accumulated other comprehensive income (loss)		261		127		522	254
Total other comprehensive income (loss), net of tax		261		127		522	254
Balance		(14,816)	(15,077)	(8,387)	(8,514)	(14,816)	(8,387)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ (21,281)	(18,554)	(21,281)	(18,163)	(11,916)	(21,281)	(11,916)
Reclassification from AOCI to retained earnings						(2,783)
Total other comprehensive income (loss), net of tax		5,394	5,510	(2,133)	(6,247)	10,904	(8,380)
Balance		$ (13,160)	$ (18,554)	$ (20,296)	$ (18,163)	$ (13,160)	$ (20,296)

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Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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