DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES - Amount of Gain (Loss) recognized in Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	$ 453	$ 478	$ (3,752)	$ (1,253)
Amount of Gain (Loss) Recognized in Income	(227)	110	(509)	136
Loss reclassification from AOCI to Earnings expected over the next 12 months			323
Designated as hedging instrument \| Cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	(835)	(644)	(2,227)	(4,588)
Amount of Gain (Loss) Recognized in Income	(107)	217	(287)	216
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	(1,056)	(644)	(981)	(4,588)
Amount of Gain (Loss) Recognized in Income	(196)	217	(384)	216
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	221		(1,246)
Amount of Gain (Loss) Recognized in Income	89		97
Designated as hedging instrument \| Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	1,288	1,122	(1,525)	3,335
Amount of Gain (Loss) Recognized in Income	(140)	(23)	(276)	(41)
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	1,288	1,122	(1,525)	3,335
Amount of Gain (Loss) Recognized in Income	(140)	(23)	(276)	(41)
Designated as hedging instrument \| Economic hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	40	(54)	50	(43)
Designated as hedging instrument \| Economic hedges \| Forward sale commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	40	(54)	50	(43)
Not designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(20)	(30)	4	4
Not designated as hedging instrument \| Interest rate lock commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ (20)	$ (30)	$ 4	$ 4

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.

+ 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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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