Loans (Recorded Investment By Loan Class In Current And Nonaccrual Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	$ 2,161	$ 3,384
60-89 Days Past Due	351	1,486
Greater Than 90 Days	9	8
Total Past Due	2,521	4,878
Nonaccrual	8,558	8,432
Current	2,072,678	2,039,290
Total loans	2,083,757	2,052,600	$ 1,892,390
Commercial Business [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	94	321
60-89 Days Past Due	2	612
Total Past Due	96	933
Nonaccrual	4,056	3,922
Current	313,268	308,620
Total loans	317,420	313,475	277,427
Commercial Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	53	68
60-89 Days Past Due		146
Total Past Due	53	214
Nonaccrual	1,781	947
Current	589,966	566,320
Total loans	591,800	567,481	480,479
Residential Real Estate Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	515	723
60-89 Days Past Due	22	395
Total Past Due	537	1,118
Nonaccrual	1,601	1,848
Current	375,268	373,057
Total loans	377,406	376,023	351,088
Residential Real Estate Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	151	199
60-89 Days Past Due	43	34
Total Past Due	194	233
Nonaccrual	165	235
Current	123,535	124,298
Total loans	123,894	124,766	126,832
Consumer Indirect [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	1,296	1,975
60-89 Days Past Due	267	286
Total Past Due	1,563	2,261
Nonaccrual	943	1,467
Current	652,842	648,766
Total loans	655,348	652,494	637,380
Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days Past Due	52	98
60-89 Days Past Due	17	13
Greater Than 90 Days	9	8
Total Past Due	78	119
Nonaccrual	12	13
Current	17,799	18,229
Total loans	$ 17,889	$ 18,361	$ 19,184

Financing receivables that are less than 60 days past due but more than 29 days past due.

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=35738203&loc=SL6953401-111524

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Financing receivables that are current.

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ 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=35738203&loc=d3e5111-111524

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 10
-Subparagraph 3
-Article 9

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