Allowance For Loan Losses (Schedule Of Aging Analysis Of Accruing And Non-Accruing Loans) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	$ 3,128,383	$ 3,106,150
Non-accrual	11,447	10,297
Gross loans	3,146,697	3,127,410
Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	1,478,137	1,458,746
Non-accrual	3,029	2,814
Gross loans	1,485,823	1,468,278
Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	143,072	138,480
Non-accrual	0	168
Gross loans	143,540	139,499
Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	212,810	206,447
Non-accrual	818	1,345
Gross loans	213,815	208,484
Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	1,259,519	1,269,520
Non-accrual	7,599	5,970
Gross loans	1,268,052	1,277,576
Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	31,829	29,108
Non-accrual	1	0
Gross loans	31,869	29,162
DDA overdrafts
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	3,016	3,849
Non-accrual	0	0
Gross loans	3,598	4,411
30-59 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	5,977	9,631
30-59 days \| Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	3,841	5,990
30-59 days \| Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	407	671
30-59 days \| Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	187	549
30-59 days \| Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	934	1,841
30-59 days \| Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	38	39
30-59 days \| DDA overdrafts
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	570	541
60-89 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	855	1,070
60-89 days \| Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	793	709
60-89 days \| Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	52	88
60-89 days \| Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	0	1
60-89 days \| Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	0	245
60-89 days \| Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	1	13
60-89 days \| DDA overdrafts
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	9	14
Over 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	35	262
Over 90 days \| Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	23	19
Over 90 days \| Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	9	92
Over 90 days \| Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	0	142
Over 90 days \| Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	0	0
Over 90 days \| Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	0	2
Over 90 days \| DDA overdrafts
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due	$ 3	$ 7

Financing receivables that are current.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 310
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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