Allowance for Loan and Lease Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Allowance for loan losses [Roll Forward]
Beginning balance	$ 35,189	$ 35,713	$ 36,151	$ 35,933	$ 35,933
Provision charged to expense	1,929	2,764	2,875	3,993	7,521
Losses charged off	(2,526)	(2,189)	(5,503)	(4,680)	(11,085)
Recoveries	1,179	845	2,248	1,887	3,782
Ending balance	35,771	37,133	35,771	37,133	36,151
Ending balance [Abstract]
Individually evaluated for impairment	907	1,319	907	1,319	991
Collectively evaluated for impairment	34,864	35,814	34,864	35,814	35,160
Loans ending balance [Abstract]
Individually evaluated for impairment	46,743	50,729	46,743	50,729	47,412
Collectively evaluated for impairment	3,122,299	3,036,613	3,122,299	3,036,613	3,075,528
Commercial [Member] \| Construction [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	686	644	686	884	884
Provision charged to expense	51	22	37	(220)	(237)
Losses charged off	0	0	0	(4)	(10)
Recoveries	3	3	17	9	49
Ending balance	740	669	740	669	686
Ending balance [Abstract]
Individually evaluated for impairment	0	25	0	25	25
Collectively evaluated for impairment	740	644	740	644	661
Loans ending balance [Abstract]
Individually evaluated for impairment	4,299	4,860	4,299	4,860	4,584
Collectively evaluated for impairment	76,897	67,194	76,897	67,194	71,895
Commercial [Member] \| Real Estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	14,133	14,177	14,509	14,191	14,191
Provision charged to expense	788	1,435	597	1,624	2,281
Losses charged off	(266)	(318)	(477)	(528)	(2,038)
Recoveries	3	5	29	12	75
Ending balance	14,658	15,299	14,658	15,299	14,509
Ending balance [Abstract]
Individually evaluated for impairment	807	1,227	807	1,227	966
Collectively evaluated for impairment	13,851	14,072	13,851	14,072	13,543
Loans ending balance [Abstract]
Individually evaluated for impairment	31,874	32,240	31,874	32,240	31,465
Collectively evaluated for impairment	1,159,837	1,146,989	1,159,837	1,146,989	1,157,215
Commercial [Member] \| Equipment Lease Financing [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	23	40	18	42	42
Provision charged to expense	(6)	(7)	(1)	(9)	(24)
Losses charged off	0	0	0	0	0
Recoveries	0	0	0	0	0
Ending balance	17	33	17	33	18
Ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	17	33	17	33	18
Loans ending balance [Abstract]
Individually evaluated for impairment	0	130	0	130	0
Collectively evaluated for impairment	2,354	4,773	2,354	4,773	3,042
Commercial [Member] \| Other [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	4,229	4,736	5,039	4,656	4,656
Provision charged to expense	668	599	16	1,019	1,744
Losses charged off	(322)	(417)	(557)	(836)	(1,893)
Recoveries	62	75	139	154	532
Ending balance	4,637	4,993	4,637	4,993	5,039
Ending balance [Abstract]
Individually evaluated for impairment	100	67	100	67	0
Collectively evaluated for impairment	4,537	4,926	4,537	4,926	5,039
Loans ending balance [Abstract]
Individually evaluated for impairment	8,949	10,850	8,949	10,850	9,481
Collectively evaluated for impairment	343,461	341,323	343,461	341,323	341,553
Residential [Member] \| Construction [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	633	571	660	629	629
Provision charged to expense	(11)	10	(14)	(48)	31
Losses charged off	(4)	0	(28)	0	0
Recoveries	0	0	0	0	0
Ending balance	618	581	618	581	660
Ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	618	581	618	581	660
Loans ending balance [Abstract]
Individually evaluated for impairment	0	846	0	846	318
Collectively evaluated for impairment	64,817	57,720	64,817	57,720	67,040
Residential [Member] \| Real Estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	5,936	5,877	5,688	6,027	6,027
Provision charged to expense	(493)	(128)	(58)	(275)	189
Losses charged off	(222)	(97)	(415)	(164)	(615)
Recoveries	13	10	19	74	87
Ending balance	5,234	5,662	5,234	5,662	5,688
Ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	5,234	5,662	5,234	5,662	5,688
Loans ending balance [Abstract]
Individually evaluated for impairment	1,621	1,803	1,621	1,803	1,564
Collectively evaluated for impairment	719,075	706,664	719,075	706,664	708,006
Residential [Member] \| Home Equity [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	862	757	857	774	774
Provision charged to expense	22	(11)	27	(27)	257
Losses charged off	(18)	0	(19)	(3)	(178)
Recoveries	0	1	1	3	4
Ending balance	866	747	866	747	857
Ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	866	747	866	747	857
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	102,432	93,721	102,432	93,721	99,356
Consumer [Member] \| Consumer Direct [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	1,798	1,844	1,863	1,885	1,885
Provision charged to expense	264	102	343	196	418
Losses charged off	(276)	(239)	(491)	(509)	(965)
Recoveries	124	159	195	294	525
Ending balance	1,910	1,866	1,910	1,866	1,863
Ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	1,910	1,866	1,910	1,866	1,863
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	145,376	135,228	145,376	135,228	137,754
Consumer [Member] \| Consumer Indirect [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	6,889	7,067	6,831	6,845	6,845
Provision charged to expense	646	742	1,928	1,733	2,862
Losses charged off	(1,418)	(1,118)	(3,516)	(2,636)	(5,386)
Recoveries	974	592	1,848	1,341	2,510
Ending balance	7,091	7,283	7,091	7,283	6,831
Ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	7,091	7,283	7,091	7,283	6,831
Loans ending balance [Abstract]
Individually evaluated for impairment	0	0	0	0	0
Collectively evaluated for impairment	$ 508,050	$ 483,001	$ 508,050	$ 483,001	$ 489,667

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.

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

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