Business Combinations, Goodwill and Intangible Assets (Schedule of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Gross Amount	$ 17,282	$ 17,073
Accumulated Amortization	(15,180)	(14,238)
Core Banking \| Core Deposit Intangible
Business Acquisition [Line Items]
Gross Amount	11,617	11,617
Accumulated Amortization	(9,694)	(8,782)
Core Banking \| Branch Acquisition Intangible
Business Acquisition [Line Items]
Gross Amount	257	257
Accumulated Amortization	(257)	(257)
Insurance \| Customer List
Business Acquisition [Line Items]
Gross Amount	5,408	5,199
Accumulated Amortization	$ (5,229)	$ (5,199)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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