DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES - Amount of Gain (Loss) recognized in Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	$ (155)	$ 997	$ 1,775	$ (5,792)
Amount of Gain (Loss) Recognized in Income	(331)	(630)	(840)	(825)
Loss reclassification from AOCI to Earnings expected over the next 12 months			1,000
Designated as hedging instrument \| Cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	66	362	1,055	(4,247)
Amount of Gain (Loss) Recognized in Income	(113)	(427)	(400)	(642)
Designated as hedging instrument \| Cash flow hedges \| Interest rate swap on deposits
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	167	362	1,148	(4,247)
Amount of Gain (Loss) Recognized in Income	(205)	(427)	(589)	(642)
Designated as hedging instrument \| Cash flow hedges \| Interest rate swap on variable rate loans
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	(101)		(93)
Amount of Gain (Loss) Recognized in Income	92		189
Designated as hedging instrument \| Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	(221)	635	720	(1,545)
Amount of Gain (Loss) Recognized in Income	(144)	(204)	(421)	(145)
Designated as hedging instrument \| Fair value hedges \| Interest rate swap on deposits
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	(221)	635	720	(1,545)
Amount of Gain (Loss) Recognized in Income	(144)	(204)	(421)	(145)
Designated as hedging instrument \| Economic hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(96)	40	(45)	(3)
Designated as hedging instrument \| Economic hedges \| Forward sale commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(96)	40	(45)	(3)
Not designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	22	(39)	26	(35)
Not designated as hedging instrument \| Interest rate lock commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ 22	$ (39)	$ 26	$ (35)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959

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The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80845-113994

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Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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-Name Accounting Standards Codification
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