Loans (Recorded Investment By Loan Class In Current And Nonaccrual Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	$ 4,734	$ 5,713
Nonaccrual	5,802	7,133
Current	3,056,460	3,031,474
Total Loans	3,066,996	3,044,320	$ 2,752,450
30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	3,320	4,761
60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,412	944
Greater than 90 Days [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	2	8
Commercial Business [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	478	228
Nonaccrual	594	912
Current	551,762	555,900
Total Loans	552,834	557,040	463,526
Commercial Business [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	328	227
Commercial Business [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	150	1
Commercial Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	818	574
Nonaccrual	909	1,586
Current	993,456	958,105
Total Loans	995,183	960,265	823,305
Commercial Mortgage [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	443	574
Commercial Mortgage [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	375
Residential Real Estate Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,291	1,537
Nonaccrual	2,225	2,391
Current	521,520	511,053
Total Loans	525,036	514,981	470,111
Residential Real Estate Loans [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	924	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	367	242
Residential Real Estate Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	165	102
Nonaccrual	252	255
Current	105,175	106,355
Total Loans	105,592	106,712	112,428
Residential Real Estate Lines [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	150	102
Residential Real Estate Lines [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	15
Consumer Indirect [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,885	3,122
Nonaccrual	1,822	1,989
Current	868,703	883,621
Total Loans	872,410	888,732	866,598
Consumer Indirect [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,388	2,424
Consumer Indirect [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	497	698
Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	97	150
Current	15,844	16,440
Total Loans	15,941	16,590	$ 16,482
Other Consumer [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	87	139
Other Consumer [Member] \| 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	8	3
Other Consumer [Member] \| Greater than 90 Days [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	$ 2	$ 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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