Allowance for Loan and Lease Losses (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Allowance for loan losses [Roll Forward]
Beginning balance	$ 34,447	$ 34,008	$ 34,008
Provision charged to expense	1,901	1,345	8,755
Losses charged off	2,636	2,545	11,436
Recoveries	894	807	3,120
Ending balance	34,606	33,615	34,447
Allowance for Loan Losses Ending balance: [Abstract]
Individually evaluated for impairment	1,787	2,135	1,742
Collectively evaluated for impairment	32,819	31,480	32,705
Loans Ending balance: [Abstract]
Individually evaluated for impairment	56,464	65,286	59,068
Collectively evaluated for impairment	2,690,018	2,520,222	2,674,756
Commercial Construction [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,896	3,396	3,396
Provision charged to expense	(34)	(296)	(513)
Losses charged off	1	0	15
Recoveries	3	7	28
Ending balance	2,864	3,107	2,896
Allowance for Loan Losses Ending balance: [Abstract]
Individually evaluated for impairment	734	939	734
Collectively evaluated for impairment	2,130	2,168	2,162
Loans Ending balance: [Abstract]
Individually evaluated for impairment	9,143	9,708	9,627
Collectively evaluated for impairment	110,079	101,564	112,315
Commercial Secured by Real Estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	13,618	14,535	14,535
Provision charged to expense	630	(106)	941
Losses charged off	433	322	2,163
Recoveries	45	76	305
Ending balance	13,860	14,183	13,618
Allowance for Loan Losses Ending balance: [Abstract]
Individually evaluated for impairment	869	1,084	827
Collectively evaluated for impairment	12,991	13,099	12,791
Loans Ending balance: [Abstract]
Individually evaluated for impairment	32,828	39,953	34,357
Collectively evaluated for impairment	933,507	834,484	914,269
Equipment Lease Financing [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	119	121	121
Provision charged to expense	6	(14)	(2)
Losses charged off	0	0	0
Recoveries	0	0	0
Ending balance	125	107	119
Allowance for Loan Losses Ending balance: [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	125	107	119
Loans Ending balance: [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	10,908	8,122	10,344
Commercial Other [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	4,263	5,238	5,238
Provision charged to expense	55	(13)	1,545
Losses charged off	441	633	3,141
Recoveries	248	162	621
Ending balance	4,125	4,754	4,263
Allowance for Loan Losses Ending balance: [Abstract]
Individually evaluated for impairment	184	112	181
Collectively evaluated for impairment	3,941	4,642	4,082
Loans Ending balance: [Abstract]
Individually evaluated for impairment	13,593	14,604	13,807
Collectively evaluated for impairment	327,807	337,044	338,241
Real Estate Construction [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	534	397	397
Provision charged to expense	75	44	258
Losses charged off	90	0	123
Recoveries	0	1	2
Ending balance	519	442	534
Allowance for Loan Losses Ending balance: [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	519	442	534
Loans Ending balance: [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	60,894	59,730	62,412
Real Estate Mortgage [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	6,094	4,939	4,939
Provision charged to expense	364	356	2,173
Losses charged off	438	164	1,058
Recoveries	10	12	40
Ending balance	6,030	5,143	6,094
Allowance for Loan Losses Ending balance: [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	6,030	5,143	6,094
Loans Ending balance: [Abstract]
Individually evaluated for impairment	900	1,021	1,277
Collectively evaluated for impairment	707,167	694,493	711,188
Home Equity [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	756	601	601
Provision charged to expense	17	51	265
Losses charged off	42	27	115
Recoveries	11	1	5
Ending balance	742	626	756
Allowance for Loan Losses Ending balance: [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	742	626	756
Loans Ending balance: [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	87,136	84,694	88,335
Consumer Direct [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	1,574	1,127	1,127
Provision charged to expense	200	753	1,207
Losses charged off	357	453	1,326
Recoveries	104	146	566
Ending balance	1,521	1,573	1,574
Allowance for Loan Losses Ending balance: [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	1,521	1,573	1,574
Loans Ending balance: [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	120,005	117,497	122,136
Consumer Indirect [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	4,593	3,654	3,654
Provision charged to expense	588	570	2,881
Losses charged off	834	946	3,495
Recoveries	473	402	1,553
Ending balance	4,820	3,680	4,593
Allowance for Loan Losses Ending balance: [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	4,820	3,680	4,593
Loans Ending balance: [Abstract]
Individually evaluated for impairment	0	0	0
Collectively evaluated for impairment	$ 332,515	$ 282,594	$ 315,516

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

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

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Amount of direct write-downs of financing receivables charged against the allowance.

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

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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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