DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES - Amount of Gain (Loss) recognized in Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	$ (2,039)	$ (1,732)
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	(283)	(64)
Amount of Gain (Loss) Recognized in Income	(283)	(64)
Loss reclassification from AOCI to Earnings expected over the next 12 months	390
Designated as hedging instrument \| Cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	774	(3,945)
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	(180)	(1)
Amount of Gain (Loss) Recognized in Income	(180)	(1)
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	987	(3,945)
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	(188)	(1)
Amount of Gain (Loss) Recognized in Income	(188)	(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	(213)
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	8
Amount of Gain (Loss) Recognized in Income	8
Designated as hedging instrument \| Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	(2,813)	2,213
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	(137)	(18)
Amount of Gain (Loss) Recognized in Income	(137)	(18)
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	(2,813)	2,213
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	(137)	(18)
Amount of Gain (Loss) Recognized in Income	(137)	(18)
Designated as hedging instrument \| Economic hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	10	(11)
Amount of Gain (Loss) Recognized in Income	10	(11)
Designated as hedging instrument \| Economic hedges \| Forward sale commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	10	(11)
Amount of Gain (Loss) Recognized in Income	10	(11)
Not designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	24	(34)
Amount of Gain (Loss) Recognized in Income	24	(34)
Not designated as hedging instrument \| Interest rate lock commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	24	(34)
Amount of Gain (Loss) Recognized in Income	$ 24	$ (34)

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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No definition available.

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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.

+ References

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669686-108580

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

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