DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Summary of Derivative Financial Instruments (Details) - Mortgages - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Other Assets
Derivative [Line Items]
Derivative, notional amount	$ 288,490	$ 81,833
Derivative, fair value	7,814	2,537
Other Liabilities
Derivative [Line Items]
Derivative, notional amount	1,814,669	163,189
Derivative, fair value	4,471	1,276
Interest rate lock commitments \| Other Assets
Derivative [Line Items]
Derivative, notional amount	288,490	81,833
Derivative, fair value	7,814	2,537
Forward contracts related to mortgage loans held for sale
Derivative [Line Items]
Derivative, notional amount	1,810,000	163,200
Forward contracts related to mortgage loans held for sale \| Other Liabilities
Derivative [Line Items]
Derivative, notional amount	1,814,669	163,189
Derivative, fair value	$ 4,471	$ 1,276

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
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Nominal or face amount used to calculate payment on derivative.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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