LOANS AND ALLOWANCE FOR LOAN LOSSES - Loan Portfolio (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Composition of loan portfolio [Abstract]
Loans, net of deferred loan fees	$ 1,538,493	$ 1,309,219
Interest receivable on loans	5,035	3,684
Total ending loans balance	1,543,528	1,312,903
Commercial and Agricultural
Composition of loan portfolio [Abstract]
Total ending loans balance	406,013	230,922
Commercial mortgages:
Composition of loan portfolio [Abstract]
Total ending loans balance	692,935	650,570
Commercial mortgages: \| Construction
Composition of loan portfolio [Abstract]
Loans, net of deferred loan fees	54,332	43,962
Total ending loans balance	54,523	44,082
Commercial mortgages: \| Commercial mortgages
Composition of loan portfolio [Abstract]
Loans, net of deferred loan fees	636,179	604,832
Total ending loans balance	638,412	606,488
Residential mortgages
Composition of loan portfolio [Abstract]
Loans, net of deferred loan fees	227,372	188,338
Total ending loans balance	227,984	188,874
Consumer loans:
Composition of loan portfolio [Abstract]
Total ending loans balance	216,596	242,537
Consumer loans: \| Home equity lines and loans
Composition of loan portfolio [Abstract]
Loans, net of deferred loan fees	81,556	91,784
Total ending loans balance	81,770	92,065
Consumer loans: \| Indirect consumer loans
Composition of loan portfolio [Abstract]
Loans, net of deferred loan fees	121,406	134,973
Total ending loans balance	121,720	135,366
Consumer loans: \| Direct consumer loans
Composition of loan portfolio [Abstract]
Loans, net of deferred loan fees	13,055	15,038
Total ending loans balance	13,106	15,106
Commercial and industrial
Composition of loan portfolio [Abstract]
Payroll Protection Program Loans - CARES Act	189,800
Commercial and industrial \| Commercial and Agricultural
Composition of loan portfolio [Abstract]
Loans, net of deferred loan fees	403,911	230,018
Total ending loans balance	405,329	230,648
Agricultural \| Commercial and Agricultural
Composition of loan portfolio [Abstract]
Loans, net of deferred loan fees	682	274
Total ending loans balance	$ 684	$ 274

Financing Receivable, after Interest Receivable on Loans, before Allowance on Credit Loss

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- Definition

Financing Receivable, Payroll Protection Program Loans - CARES Act

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
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- Definition

Amount, before allowance for credit loss, of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
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