Allowance for Loan and Lease Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Allowance for loan losses [Roll Forward]
Beginning balance	$ 34,998	$ 35,771	$ 35,908	$ 36,151	$ 36,151
Provision charged to expense	1,253	1,543	3,006	4,418	6,167
Losses charged off	(2,316)	(2,828)	(7,168)	(8,331)	(10,998)
Recoveries	876	1,305	3,065	3,553	4,588
Ending balance	34,811	35,791	34,811	35,791	35,908
Ending balance [Abstract]
Individually evaluated for impairment	672	736	672	736	801
Collectively evaluated for impairment	34,139	35,055	34,139	35,055	35,107
Loans ending balance [Abstract]
Individually evaluated for impairment	56,315	46,883	56,315	46,883	46,366
Collectively evaluated for impairment	3,158,470	3,131,005	3,158,470	3,131,005	3,162,272
Commercial [Member] \| Construction [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	799	740	862	686	686
Provision charged to expense	299	54	301	91	115
Losses charged off	(1)	0	(72)	0	0
Recoveries	3	23	9	40	61
Ending balance	1,100	817	1,100	817	862
Ending balance [Abstract]
Individually evaluated for impairment	99	0	99	0	50
Collectively evaluated for impairment	1,001	817	1,001	817	812
Loans ending balance [Abstract]
Individually evaluated for impairment	2,974	2,804	2,974	2,804	4,227
Collectively evaluated for impairment	90,560	78,668	90,560	78,668	78,488
Commercial [Member] \| Real Estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	15,098	14,658	14,531	14,509	14,509
Provision charged to expense	(742)	298	79	895	786
Losses charged off	(21)	(460)	(401)	(937)	(988)
Recoveries	40	142	166	171	224
Ending balance	14,375	14,638	14,375	14,638	14,531
Ending balance [Abstract]
Individually evaluated for impairment	398	641	398	641	605
Collectively evaluated for impairment	13,977	13,997	13,977	13,997	13,926
Loans ending balance [Abstract]
Individually evaluated for impairment	39,986	33,612	39,986	33,612	31,499
Collectively evaluated for impairment	1,134,778	1,150,020	1,134,778	1,150,020	1,151,594
Commercial [Member] \| Equipment Lease Financing [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	7	17	12	18	18
Provision charged to expense	(2)	(2)	(7)	(3)	(6)
Losses charged off	0	0	0	0	0
Recoveries	0	0	0	0	0
Ending balance	5	15	5	15	12
Ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	5	15	5	15	12
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	651	1,986	651	1,986	1,740
Commercial [Member] \| Other [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	4,889	4,637	4,993	5,039	5,039
Provision charged to expense	1,436	82	2,055	98	824
Losses charged off	(638)	(521)	(1,703)	(1,078)	(1,513)
Recoveries	75	407	417	546	643
Ending balance	5,762	4,605	5,762	4,605	4,993
Ending balance [Abstract]
Individually evaluated for impairment	175	95	175	95	146
Collectively evaluated for impairment	5,587	4,510	5,587	4,510	4,847
Loans ending balance [Abstract]
Individually evaluated for impairment	11,037	8,589	11,037	8,589	8,758
Collectively evaluated for impairment	377,495	338,056	377,495	338,056	368,440
Residential [Member] \| Construction [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	358	618	512	660	660
Provision charged to expense	(28)	(44)	(181)	(58)	(115)
Losses charged off	0	0	(1)	(28)	(33)
Recoveries	0	0	0	0	0
Ending balance	330	574	330	574	512
Ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	330	574	330	574	512
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	62,859	61,782	62,859	61,782	57,160
Residential [Member] \| Real Estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	4,187	5,234	4,433	5,688	5,688
Provision charged to expense	705	(566)	726	(625)	(336)
Losses charged off	(384)	(136)	(684)	(550)	(1,004)
Recoveries	10	7	43	26	85
Ending balance	4,518	4,539	4,518	4,539	4,433
Ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	4,518	4,539	4,518	4,539	4,433
Loans ending balance [Abstract]
Individually evaluated for impairment	2,318	1,878	2,318	1,878	1,882
Collectively evaluated for impairment	720,314	720,144	720,314	720,144	720,535
Residential [Member] \| Home Equity [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	933	866	841	857	857
Provision charged to expense	32	(9)	181	18	39
Losses charged off	(40)	(19)	(99)	(38)	(69)
Recoveries	2	4	4	5	14
Ending balance	927	842	927	842	841
Ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	927	842	927	842	841
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	110,663	103,805	110,663	103,805	106,299
Consumer [Member] \| Consumer Direct [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	1,767	1,910	1,883	1,863	1,863
Provision charged to expense	104	59	385	402	572
Losses charged off	(218)	(196)	(795)	(687)	(997)
Recoveries	82	133	262	328	445
Ending balance	1,735	1,906	1,735	1,906	1,883
Ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	1,735	1,906	1,735	1,906	1,883
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	149,500	146,002	149,500	146,002	144,289
Consumer [Member] \| Consumer Indirect [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	6,960	7,091	7,841	6,831	6,831
Provision charged to expense	(551)	1,671	(533)	3,600	4,288
Losses charged off	(1,014)	(1,496)	(3,413)	(5,013)	(6,394)
Recoveries	664	589	2,164	2,437	3,116
Ending balance	6,059	7,855	6,059	7,855	7,841
Ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	6,059	7,855	6,059	7,855	7,841
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	$ 511,650	$ 530,542	$ 511,650	$ 530,542	$ 533,727

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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- 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.

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

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