Allowance for Loan and Lease Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance for loan losses [Roll Forward]
Beginning balance	$ 35,933	$ 36,094	$ 34,447
Provision charged to expense	7,521	7,872	8,650
Losses charged off	(11,085)	(11,668)	(9,870)
Recoveries	3,782	3,635	2,867
Ending balance	36,151	35,933	36,094
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	991	1,313	2,461
Collectively evaluated for impairment	35,160	34,620	33,633
Loans ending balance [Abstract]
Individually evaluated for impairment	47,412	52,202	49,888
Collectively evaluated for impairment	3,075,528	2,886,169	2,824,073
Commercial [Member] \| Construction [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	884	2,199	2,896
Provision charged to expense	(237)	(1,035)	(707)
Losses charged off	(10)	(316)	(3)
Recoveries	49	36	13
Ending balance	686	884	2,199
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	25	213	831
Collectively evaluated for impairment	661	671	1,368
Loans ending balance [Abstract]
Individually evaluated for impairment	4,584	5,609	6,263
Collectively evaluated for impairment	71,895	61,389	71,757
Commercial [Member] \| Real Estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	14,191	14,434	13,618
Provision charged to expense	2,281	1,220	2,135
Losses charged off	(2,038)	(1,641)	(1,379)
Recoveries	75	178	60
Ending balance	14,509	14,191	14,434
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	966	1,035	1,227
Collectively evaluated for impairment	13,543	13,156	13,207
Loans ending balance [Abstract]
Individually evaluated for impairment	31,465	33,756	33,421
Collectively evaluated for impairment	1,157,215	1,051,672	1,019,498
Commercial [Member] \| Equipment Lease Financing [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	42	79	119
Provision charged to expense	(24)	(37)	(40)
Losses charged off	0	0	0
Recoveries	0	0	0
Ending balance	18	42	79
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	18	42	79
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	3,042	5,512	8,514
Commercial [Member] \| Other [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	4,656	4,225	4,263
Provision charged to expense	1,744	2,128	1,338
Losses charged off	(1,893)	(2,136)	(1,961)
Recoveries	532	439	585
Ending balance	5,039	4,656	4,225
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	65	403
Collectively evaluated for impairment	5,039	4,591	3,822
Loans ending balance [Abstract]
Individually evaluated for impairment	9,481	11,354	8,460
Collectively evaluated for impairment	341,553	338,805	350,438
Residential [Member] \| Construction [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	629	550	534
Provision charged to expense	31	264	147
Losses charged off	0	(192)	(135)
Recoveries	0	7	4
Ending balance	660	629	550
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	660	629	550
Loans ending balance [Abstract]
Individually evaluated for impairment	318	0	0
Collectively evaluated for impairment	67,040	57,966	61,750
Residential [Member] \| Real Estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	6,027	6,678	6,094
Provision charged to expense	189	291	1,888
Losses charged off	(615)	(1,043)	(1,421)
Recoveries	87	101	117
Ending balance	5,688	6,027	6,678
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	5,688	6,027	6,678
Loans ending balance [Abstract]
Individually evaluated for impairment	1,564	1,483	1,744
Collectively evaluated for impairment	708,006	701,486	706,130
Residential [Member] \| Home Equity [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	774	839	756
Provision charged to expense	257	(20)	158
Losses charged off	(178)	(54)	(129)
Recoveries	4	9	54
Ending balance	857	774	839
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	857	774	839
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	99,356	91,511	89,450
Consumer [Member] \| Consumer Direct [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	1,885	1,594	1,574
Provision charged to expense	418	912	891
Losses charged off	(965)	(1,236)	(1,306)
Recoveries	525	615	435
Ending balance	1,863	1,885	1,594
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	1,863	1,885	1,594
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	137,754	133,093	126,406
Consumer [Member] \| Consumer Indirect [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	6,845	5,496	4,593
Provision charged to expense	2,862	4,149	2,840
Losses charged off	(5,386)	(5,050)	(3,536)
Recoveries	2,510	2,250	1,599
Ending balance	6,831	6,845	5,496
Allowance for loan losses ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	6,831	6,845	5,496
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	$ 489,667	$ 444,735	$ 390,130

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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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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