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, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	$ (2,612)	$ (1,206)	$ (1,776)	$ (4,192)
Amount of Gain (Loss) Recognized in Income	629	26	1,603	(578)
Designated as hedging instrument \| Cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	(516)	81	(608)	569
Amount of Gain (Loss) Recognized in Income	238	(98)	650	(240)
Designated as hedging instrument \| Cash flow hedges \| Interest rate swap on wholesale funding
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	(564)	1,262	(786)	4,058
Amount of Gain (Loss) Recognized in Income	816	140	2,225	(1)
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	48	(1,181)	178	(3,489)
Amount of Gain (Loss) Recognized in Income	(578)	(238)	(1,575)	(239)
Designated as hedging instrument \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	(2,096)	(1,287)	(1,168)	(4,761)
Amount of Gain (Loss) Recognized in Income	369	155	985	(48)
Designated as hedging instrument \| Fair Value Hedging \| Interest rate swap on deposits
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	(2,096)	(1,287)	(1,168)	(4,761)
Amount of Gain (Loss) Recognized in Income	369	155	985	(48)
Designated as hedging instrument \| Economic hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(2)	19	47	(7)
Designated as hedging instrument \| Economic hedges \| Forward sale commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(2)	19	47	(7)
Not designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	24	(50)	(79)	(283)
Not designated as hedging instrument \| Interest Rate Lock Commitment
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ 24	$ (50)	$ (79)	$ (283)

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4E
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4E

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-Publisher FASB
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