Loans (Recorded Investment By Loan Class In Current And Nonaccrual Loans) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	$ 8,067	$ 5,713
Nonaccrual	11,458	7,133
Current	3,090,539	3,031,474
Total Loans	3,110,064	3,044,320	$ 2,858,843
30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	7,171	4,761
60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	891	944
Greater than 90 Days [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	5	8
Commercial Business [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	2,461	228
Nonaccrual	638	912
Current	591,022	555,900
Total Loans	594,121	557,040	506,265
Commercial Business [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	2,346	227
Commercial Business [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	115	1
Commercial Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,890	574
Nonaccrual	6,836	1,586
Current	1,003,199	958,105
Total Loans	1,011,925	960,265	869,192
Commercial Mortgage [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,741	574
Commercial Mortgage [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	149
Residential Real Estate Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,025	1,537
Nonaccrual	2,283	2,391
Current	532,565	511,053
Total Loans	535,873	514,981	481,841
Residential Real Estate Loans [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	916	1,295
Residential Real Estate Loans [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	109	242
Residential Real Estate Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	174	102
Nonaccrual	282	255
Current	104,481	106,355
Total Loans	104,937	106,712	110,319
Residential Real Estate Lines [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	77	102
Residential Real Estate Lines [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	97
Consumer Indirect [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	2,428	3,122
Nonaccrual	1,399	1,989
Current	843,002	883,621
Total Loans	846,829	888,732	874,718
Consumer Indirect [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	2,009	2,424
Consumer Indirect [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	419	698
Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	89	150
Nonaccrual	20
Current	16,270	16,440
Total Loans	16,379	16,590	$ 16,508
Other Consumer [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	82	139
Other Consumer [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	2	3
Other Consumer [Member] \| Greater than 90 Days [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	$ 5	$ 8

Financing receivables that are current.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
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