Loans, Major Classifications of Loans, Net of Income and Deferred Loan Origination Cost (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) Segment	Dec. 31, 2016 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 3,122,940	$ 2,938,371
Number of portfolio segments \| Segment	9
Loans held for sale [Abstract]
Loans held for sale	$ 1,033	1,244
Commercial [Member] \| Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	76,479	66,998
Commercial [Member] \| Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,188,680	1,085,428
Commercial [Member] \| Equipment Lease Financing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	3,042	5,512
Commercial [Member] \| Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	351,034	350,159
Residential [Member] \| Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	67,358	57,966
Residential [Member] \| Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	709,570	702,969
Residential [Member] \| Home Equity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	99,356	91,511
Consumer [Member] \| Consumer Direct [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	137,754	133,093
Consumer [Member] \| Consumer Indirect [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 489,667	$ 444,735

Number of portfolio segments through which the Company segregates and evaluates its loan portfolio.

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- Definition

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+ References

No definition available.

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes 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
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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- Definition

Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

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