Loans (Recorded Investment By Loan Class In Current And Nonaccrual Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	$ 4,322	$ 5,893
Nonaccrual	8,010	6,317
Current	2,354,308	2,292,861
Total loans	2,366,640	2,305,071	$ 2,083,757
30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	3,639	5,128
60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	673	756
Greater than 90 Days [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	10	9
Commercial Business [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,073	1,337
Nonaccrual	3,753	2,151
Current	370,166	345,591
Total loans	374,992	349,079	317,420
Commercial Business [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	976	1,337
Commercial Business [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	97
Commercial Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	99	48
Nonaccrual	1,267	1,025
Current	675,089	670,479
Total loans	676,455	671,552	591,800
Commercial Mortgage [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	99	48
Residential Real Estate Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,250	1,326
Nonaccrual	1,601	1,236
Current	418,763	418,914
Total loans	421,614	421,476	377,406
Residential Real Estate Loans [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,052	1,073
Residential Real Estate Loans [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	198	253
Residential Real Estate Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	265	216
Nonaccrual	336	372
Current	117,455	119,157
Total loans	118,056	119,745	123,894
Residential Real Estate Lines [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	202	216
Residential Real Estate Lines [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	63
Consumer Indirect [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,542	2,808
Nonaccrual	1,040	1,526
Current	756,179	721,420
Total loans	758,761	725,754	655,348
Consumer Indirect [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,239	2,320
Consumer Indirect [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	303	488
Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	93	158
Nonaccrual	13	7
Current	16,656	17,300
Total loans	16,762	17,465	$ 17,889
Other Consumer [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	71	134
Other Consumer [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	12	15
Other Consumer [Member] \| Greater than 90 Days [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	$ 10	$ 9

Financing receivables that are current.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953401-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5111-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(3))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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