LOANS AND ALLOWANCE FOR LOAN LOSSES - Loan Portfolio (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees	$ 1,311,824	$ 1,200,290
Interest receivable on loans	3,758	3,192
Total ending loans balance	1,315,582	1,203,482
Residential mortgages held for sale	542	412
Commercial, and Agricultural
Composition of loan portfolio [Abstract]
Total ending loans balance	199,576	177,027
Commercial mortgages:
Composition of loan portfolio [Abstract]
Total ending loans balance	646,174	570,156
Commercial mortgages: \| Construction
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees	45,558	46,387
Total ending loans balance	45,688	46,510
Commercial mortgages: \| Commercial mortgages
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees	598,772	522,269
Total ending loans balance	600,486	523,646
Residential Mortgages
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees	194,440	198,493
Total ending loans balance	194,937	198,965
Loans pledged as collateral	149,700	158,000
Consumer Loans
Composition of loan portfolio [Abstract]
Total ending loans balance	274,895	257,334
Consumer Loans \| Credit cards
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees	1,517	1,476
Total ending loans balance	1,516	1,476
Consumer Loans \| Home equity lines and loans
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees	100,591	98,590
Total ending loans balance	100,878	98,853
Consumer Loans \| Indirect Consumer Loans
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees	153,060	139,572
Total ending loans balance	153,532	139,993
Consumer Loans \| Direct consumer loans
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees	18,879	16,942
Total ending loans balance	18,969	17,012
Commercial and industrial \| Commercial, and Agricultural
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees	198,463	176,201
Total ending loans balance	199,030	176,666
Agricultural \| Commercial, and Agricultural
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees	544	360
Total ending loans balance	$ 546	$ 361

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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No definition available.

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5086-111524

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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.

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Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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