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Accumulated Other Comprehensive Income (Loss) (Components Of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands		3 Months Ended
	Jan. 01, 2019	Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 396,293	$ 396,293	$ 381,177
Reclassification from AOCI to retained earnings	2,800
Other comprehensive income (loss) before reclassifications		5,119	(6,435)
Amounts reclassified from accumulated other comprehensive income (loss)		391	188
Total other comprehensive income (loss), net of tax		5,510	(6,247)
Balance		408,253	380,302
Hedging Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(276)	(276)
Other comprehensive income (loss) before reclassifications		(254)	(104)
Total other comprehensive income (loss), net of tax		(254)	(104)
Balance		(530)	(104)
Securities Available-For-Sale and Transferred Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(7,769)	(7,769)	(3,275)
Reclassification from AOCI to retained earnings		(681)
Other comprehensive income (loss) before reclassifications		5,373	(6,331)
Amounts reclassified from accumulated other comprehensive income (loss)		130	61
Total other comprehensive income (loss), net of tax		5,503	(6,270)
Balance		(2,947)	(9,545)
Pension And Post-Retirement Obligations [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(13,236)	(13,236)	(8,641)
Reclassification from AOCI to retained earnings		(2,102)
Amounts reclassified from accumulated other comprehensive income (loss)		261	127
Total other comprehensive income (loss), net of tax		261	127
Balance		(15,077)	(8,514)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ (21,281)	(21,281)	(11,916)
Reclassification from AOCI to retained earnings		(2,783)
Total other comprehensive income (loss), net of tax		5,510	(6,247)
Balance		$ (18,554)	$ (18,163)

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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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