LOANS AND ALLOWANCE FOR LOAN LOSSES - Troubled Debt Restructuring (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($) loan	Jun. 30, 2020 USD ($) borrower	Jun. 30, 2021 USD ($) loan	Jun. 30, 2020 USD ($) borrower
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans	2	12	4	12
Pre-Modification Outstanding Recorded Investment	$ 3,606	$ 3,641	$ 6,094	$ 3,641
Post-Modification Outstanding Recorded Investment	$ 3,606	$ 3,641	$ 6,094	$ 3,641
Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| borrower		2		2
Pre-Modification Outstanding Recorded Investment		$ 929		$ 929
Post-Modification Outstanding Recorded Investment		$ 929		$ 929
Commercial loan portfolio \| Commercial mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans	2	4	4	4
Pre-Modification Outstanding Recorded Investment	$ 3,606	$ 1,297	$ 6,094	$ 1,297
Post-Modification Outstanding Recorded Investment	$ 3,606	$ 1,297	$ 6,094	$ 1,297
Residential mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| borrower		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 \| borrower		3		3
Pre-Modification Outstanding Recorded Investment		$ 738		$ 738
Post-Modification Outstanding Recorded Investment		$ 738		$ 738

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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=123577603&loc=SL6953676-111524

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

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

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