DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES - Amount of Gain (Loss) recognized in Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	$ 2,892	$ 1,768
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	(3,935)	3,156
Amount of Gain (Loss) Recognized in Income	(1,158)	(630)
Designated as hedging instrument \| Cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	(2,566)	2,291
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	(3,935)	3,156
Amount of Gain (Loss) Recognized in Income	(829)	(605)
Designated as hedging instrument \| Cash flow hedges \| Interest rate swap on deposits
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income		(2)
Designated as hedging instrument \| Cash flow hedges \| Interest rate cap agreements
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	(2,566)	2,291
Amount of Gain (Loss) Reclassified from Other Comprehensive Income	(3,935)	3,156
Amount of Gain (Loss) Recognized in Income	(829)	(603)
Designated as hedging instrument \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	5,458	(523)
Amount of Gain (Loss) Recognized in Income	(281)	7
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	5,458	(523)
Amount of Gain (Loss) Recognized in Income	(281)	7
Designated as hedging instrument \| Economic hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(11)	(84)
Designated as hedging instrument \| Economic hedges \| Forward sale commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(11)	(84)
Not designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(37)	52
Not designated as hedging instrument \| Interest Rate Lock Commitment
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ (37)	$ 52

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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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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