DERIVATIVE FINANCIAL INSTRUMENTS - Effect of Derivative Instruments on the Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Derivative [Line Items]
Amount of (Loss) or Gain Recognized in OCI on Derivative (Effective Portion)	$ (25)	$ 1,007	$ 1,560	$ 1,637
Interest income \| Interest Rate Products
Derivative [Line Items]
Amount of (Loss) or Gain Recognized in OCI on Derivative (Effective Portion)	(25)	1,007	1,560	1,637
Derivatives not designated as hedging instruments
Derivative [Line Items]
Amount of Gain or (Loss) Recognized in Income	739	55	(257)	453
Derivatives not designated as hedging instruments \| Mortgage banking activities, net \| Interest rate lock commitments with customers
Derivative [Line Items]
Amount of Gain or (Loss) Recognized in Income	3,178	542	6,227	1,174
Derivatives not designated as hedging instruments \| Mortgage banking activities, net \| Forward sale commitments
Derivative [Line Items]
Amount of Gain or (Loss) Recognized in Income	$ (2,439)	$ (487)	$ (6,484)	$ (721)

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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Amount, after tax and before reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e637-108580

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