DERIVATIVE FINANCIAL INSTRUMENTS - Effect of Derivative Instruments on the Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Derivative [Line Items]
Amount of (Loss) or Gain Recognized in OCI on Derivative (Effective Portion)	$ 1,585	$ 630
Interest income \| Interest Rate Products
Derivative [Line Items]
Amount of (Loss) or Gain Recognized in OCI on Derivative (Effective Portion)	1,585	630
Derivatives not designated as hedging instruments
Derivative [Line Items]
Amount of Gain or (Loss) Recognized in Income	(996)	398
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	3,049	632
Derivatives not designated as hedging instruments \| Mortgage banking activities, net \| Forward sale commitments
Derivative [Line Items]
Amount of Gain or (Loss) Recognized in Income	$ (4,045)	$ (234)

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=109980867&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=118930883&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=118930883&loc=d3e637-108580

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