Loans (Recorded Investment By Loan Class In Current And Nonaccrual Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	$ 5,713	$ 6,522
Nonaccrual	7,133	12,520
Current	3,031,474	2,675,880
Total Loans	3,044,320	2,694,922	$ 2,305,071
Commercial Business [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	228	100
Nonaccrual	912	5,344
Current	555,900	444,319
Total Loans	557,040	449,763	349,079
Commercial Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	574	431
Nonaccrual	1,586	2,623
Current	958,105	807,797
Total Loans	960,265	810,851	671,552
Residential Real Estate Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,537	1,964
Nonaccrual	2,391	2,252
Current	511,053	453,545
Total Loans	514,981	457,761	421,476
Residential Real Estate Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	102	349
Nonaccrual	255	404
Current	106,355	112,669
Total Loans	106,712	113,422	119,745
Consumer Indirect [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	3,122	3,478
Nonaccrual	1,989	1,895
Current	883,621	840,309
Total Loans	888,732	845,682	725,754
Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	150	200
Nonaccrual		2
Current	16,440	17,241
Total Loans	16,590	17,443	$ 17,465
30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	4,761	5,357
30 to 59 Days Past Due [Member] \| Commercial Business [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	227	64
30 to 59 Days Past Due [Member] \| Commercial Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	574	56
30 to 59 Days Past Due [Member] \| Residential Real Estate Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,295	1,908
30 to 59 Days Past Due [Member] \| Residential Real Estate Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	102	349
30 to 59 Days Past Due [Member] \| Consumer Indirect [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	2,424	2,806
30 to 59 Days Past Due [Member] \| Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	139	174
60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	944	1,154
60 to 89 Days Past Due [Member] \| Commercial Business [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1	36
60 to 89 Days Past Due [Member] \| Commercial Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans		375
60 to 89 Days Past Due [Member] \| Residential Real Estate Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	242	56
60 to 89 Days Past Due [Member] \| Consumer Indirect [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	698	672
60 to 89 Days Past Due [Member] \| Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	3	15
Greater than 90 Days [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	8	11
Greater than 90 Days [Member] \| Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	$ 8	$ 11

Financing receivables that are current.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 210
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