Allowance for Loan Losses (Allowance for Loan Losses Rollforward Analysis) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	$ 27,072	$ 26,488	$ 26,004
Charge-offs	(2,020)	(1,187)	(2,462)
Recoveries	387	221	346
Provision	1,575	1,550	2,600
Ending Balance	27,014	27,072	26,488
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	15,381	12,729	11,166
Charge-offs	(1,028)	(627)	(1,867)
Recoveries	125	25	82
Provision	263	3,254	3,348
Ending Balance	14,741	15,381	12,729
Commercial & Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	5,847	5,580	6,992
Charge-offs	(21)	(10)	(336)
Recoveries	168	119	169
Provision	(2,073)	158	(1,245)
Ending Balance	3,921	5,847	5,580
Total Commercial [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	21,228	18,309	18,158
Charge-offs	(1,049)	(637)	(2,203)
Recoveries	293	144	251
Provision	(1,810)	3,412	2,103
Ending Balance	18,662	21,228	18,309
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	3,987	5,427	5,252
Charge-offs	(486)	(250)	(74)
Recoveries	0	21	39
Provision	3,114	(1,211)	210
Ending Balance	6,615	3,987	5,427
Home Equity [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	1,603	2,412	1,889
Charge-offs	(390)	(193)	(79)
Recoveries	72	29	33
Provision	105	(645)	569
Ending Balance	1,390	1,603	2,412
Other Consumer [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	254	340	705
Charge-offs	(95)	(107)	(106)
Recoveries	22	27	23
Provision	166	(6)	(282)
Ending Balance	347	254	340
Total Consumer [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	1,857	2,752	2,594
Charge-offs	(485)	(300)	(185)
Recoveries	94	56	56
Provision	271	(651)	287
Ending Balance	$ 1,737	$ 1,857	$ 2,752

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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