Allowance for Loan and Lease Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for loan losses [Roll Forward]
Beginning balance	$ 36,151	$ 35,933	$ 36,094
Provision charged to expense	6,167	7,521	7,872
Losses charged off	(10,998)	(11,085)	(11,668)
Recoveries	4,588	3,782	3,635
Ending balance	35,908	36,151	35,933
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	801	991	1,313
Collectively evaluated for impairment	35,107	35,160	34,620
Loans ending balance [Abstract]
Individually evaluated for impairment	46,366	47,412	52,202
Collectively evaluated for impairment	3,162,272	3,075,528	2,886,169
Commercial [Member] \| Construction [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	686	884	2,199
Provision charged to expense	115	(237)	(1,035)
Losses charged off	0	(10)	(316)
Recoveries	61	49	36
Ending balance	862	686	884
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	50	25	213
Collectively evaluated for impairment	812	661	671
Loans ending balance [Abstract]
Individually evaluated for impairment	4,227	4,584	5,609
Collectively evaluated for impairment	78,488	71,895	61,389
Commercial [Member] \| Real Estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	14,509	14,191	14,434
Provision charged to expense	786	2,281	1,220
Losses charged off	(988)	(2,038)	(1,641)
Recoveries	224	75	178
Ending balance	14,531	14,509	14,191
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	605	966	1,035
Collectively evaluated for impairment	13,926	13,543	13,156
Loans ending balance [Abstract]
Individually evaluated for impairment	31,499	31,465	33,756
Collectively evaluated for impairment	1,151,594	1,157,215	1,051,672
Commercial [Member] \| Equipment Lease Financing [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	18	42	79
Provision charged to expense	(6)	(24)	(37)
Losses charged off	0	0	0
Recoveries	0	0	0
Ending balance	12	18	42
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	12	18	42
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	1,740	3,042	5,512
Commercial [Member] \| Other [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	5,039	4,656	4,225
Provision charged to expense	824	1,744	2,128
Losses charged off	(1,513)	(1,893)	(2,136)
Recoveries	643	532	439
Ending balance	4,993	5,039	4,656
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	146	0	65
Collectively evaluated for impairment	4,847	5,039	4,591
Loans ending balance [Abstract]
Individually evaluated for impairment	8,758	9,481	11,354
Collectively evaluated for impairment	368,440	341,553	338,805
Residential [Member] \| Construction [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	660	629	550
Provision charged to expense	(115)	31	264
Losses charged off	(33)	0	(192)
Recoveries	0	0	7
Ending balance	512	660	629
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	512	660	629
Loans ending balance [Abstract]
Individually evaluated for impairment	0	318	0
Collectively evaluated for impairment	57,160	67,040	57,966
Residential [Member] \| Real Estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	5,688	6,027	6,678
Provision charged to expense	(336)	189	291
Losses charged off	(1,004)	(615)	(1,043)
Recoveries	85	87	101
Ending balance	4,433	5,688	6,027
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	4,433	5,688	6,027
Loans ending balance [Abstract]
Individually evaluated for impairment	1,882	1,564	1,483
Collectively evaluated for impairment	720,535	708,006	701,486
Residential [Member] \| Home Equity [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	857	774	839
Provision charged to expense	39	257	(20)
Losses charged off	(69)	(178)	(54)
Recoveries	14	4	9
Ending balance	841	857	774
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	841	857	774
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	106,299	99,356	91,511
Consumer [Member] \| Consumer Direct [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	1,863	1,885	1,594
Provision charged to expense	572	418	912
Losses charged off	(997)	(965)	(1,236)
Recoveries	445	525	615
Ending balance	1,883	1,863	1,885
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	1,883	1,863	1,885
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	144,289	137,754	133,093
Consumer [Member] \| Consumer Indirect [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	6,831	6,845	5,496
Provision charged to expense	4,288	2,862	4,149
Losses charged off	(6,394)	(5,386)	(5,050)
Recoveries	3,116	2,510	2,250
Ending balance	7,841	6,831	6,845
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	7,841	6,831	6,845
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	$ 533,727	$ 489,667	$ 444,735

No definition available.

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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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 loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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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 to estimated loss from loan and lease transactions.

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