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LOANS AND ALLOWANCE FOR LOAN LOSSES - Troubled Debt Restructuring (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020 USD ($) loan	Jun. 30, 2020 USD ($) loan	Jun. 30, 2019 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans | loan	12	12	1
Pre-modification outstanding recorded investment	$ 3,641	$ 3,641	$ 137
Post-modification outstanding recorded investment	$ 3,641	$ 3,641	$ 137
Commercial and agricultural | Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans | loan	2	2
Pre-modification outstanding recorded investment	$ 929	$ 929
Post-modification outstanding recorded investment	$ 929	$ 929
Commercial loan portfolio | Commercial mortgages, other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans | loan	4	4
Pre-modification outstanding recorded investment	$ 1,297	$ 1,297
Post-modification outstanding recorded investment	$ 1,297	$ 1,297
Commercial loan portfolio | Residential mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans | loan	3	3
Pre-modification outstanding recorded investment	$ 677	$ 677
Post-modification outstanding recorded investment	$ 677	$ 677
Consumer Loans | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans | loan	3	3	1
Pre-modification outstanding recorded investment	$ 738	$ 738	$ 137
Post-modification outstanding recorded investment	$ 738	$ 738	$ 137

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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