LOANS - TDRs by portfolio - restructured and subsequently defaulted (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) loan	Mar. 31, 2019 USD ($) loan
Troubled debt restructurings:
Number of loans \| loan	6	12
Pre-modification outstanding balance	$ 675	$ 2,225
Post-modification outstanding balance	$ 670	$ 2,092
Troubled debt restructurings that subsequently defaulted
Number of loans \| loan		1
Recorded balance		$ 43
Commercial real estate \| Commercial Portfolio
Troubled debt restructurings:
Number of loans \| loan		3
Pre-modification outstanding balance		$ 1,924
Post-modification outstanding balance		$ 1,838
Constructions \| Commercial Portfolio
Troubled debt restructurings:
Number of loans \| loan		1
Pre-modification outstanding balance		$ 62
Post-modification outstanding balance		$ 17
Troubled debt restructurings that subsequently defaulted
Number of loans \| loan		1
Recorded balance		$ 43
Residential real estate \| Other loan portfolio
Troubled debt restructurings:
Number of loans \| loan	6	7
Pre-modification outstanding balance	$ 675	$ 224
Post-modification outstanding balance	$ 670	$ 222
Consumer \| Other loan portfolio
Troubled debt restructurings:
Number of loans \| loan		1
Pre-modification outstanding balance		$ 15
Post-modification outstanding balance		$ 15

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

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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.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 310
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