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Loans (Retail Loan Portfolio Categorized By Payment Status) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 2,752,450	$ 2,694,922
Residential Real Estate Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	470,111	457,761
Residential Real Estate Loans [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	467,887	455,509
Residential Real Estate Loans [Member] | Non-Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,224	2,252
Residential Real Estate Lines [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	112,428	113,422
Residential Real Estate Lines [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	112,056	113,018
Residential Real Estate Lines [Member] | Non-Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	372	404
Consumer Indirect [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	866,598	845,682
Consumer Indirect [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	865,131	843,787
Consumer Indirect [Member] | Non-Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,467	1,895
Other Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	16,482	17,443
Other Consumer [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	16,450	17,430
Other Consumer [Member] | Non-Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 32	$ 13

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+ References

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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