Accumulated Other Comprehensive Loss ("AOCL") (Schedule of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Balance, Beginning	$ (21,465)
Reclassification of certain tax effects	0
Balance, Ending	(24,593)	$ (21,465)
Investment securities- with OTTI [Member]
Balance, Beginning		(2,368)	$ (1,942)
Other comprehensive income/(loss) before reclassifications		31	(421)
Amounts reclassified from accumulated other comprehensive loss		(121)	(5)
Reclassification of certain tax effects	(481)
Balance, Ending	(2,939)		(2,368)
Investment Securities -All Other AFS [Member]
Balance, Beginning		(3,218)	(2,024)
Other comprehensive income/(loss) before reclassifications		638	(929)
Amounts reclassified from accumulated other comprehensive loss		36	(265)
Reclassification of certain tax effects	(435)
Balance, Ending	(2,979)		(3,218)
Investment Securities HTM [Member]
Balance, Beginning		(1,354)	(1,971)
Other comprehensive income/(loss) before reclassifications		0	0
Amounts reclassified from accumulated other comprehensive loss		253	617
Reclassification of certain tax effects	(246)
Balance, Ending	(1,347)		(1,354)
Cash Flow Hedge (OCI) [Member]
Balance, Beginning		422	(39)
Other comprehensive income/(loss) before reclassifications		59	461
Amounts reclassified from accumulated other comprehensive loss		0	0
Reclassification of certain tax effects	101
Balance, Ending	582		422
Pension Plan [Member]
Balance, Beginning		(14,232)	(12,663)
Other comprehensive income/(loss) before reclassifications		(445)	(2,086)
Amounts reclassified from accumulated other comprehensive loss		781	517
Reclassification of certain tax effects	(3,170)
Balance, Ending	(17,066)		(14,232)
SERP [Member]
Balance, Beginning		(715)	(305)
Other comprehensive income/(loss) before reclassifications		(82)	(466)
Amounts reclassified from accumulated other comprehensive loss		105	56
Reclassification of certain tax effects	(152)
Balance, Ending	(844)		(715)
Accumulated Other Comprehensive Loss [Member]
Balance, Beginning		(21,465)	(18,944)
Other comprehensive income/(loss) before reclassifications		201	(3,441)
Amounts reclassified from accumulated other comprehensive loss		$ 1,054	920
Reclassification of certain tax effects	(4,383)
Balance, Ending	$ (24,593)		$ (21,465)

Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax liability and asset pursuant to Tax Cuts and Jobs Act of 2017.

No definition available.

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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e637-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e681-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=66004921&loc=d3e1436-108581

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=66004921&loc=d3e1436-108581

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