DERIVATIVE FINANCIAL INSTRUMENTS - Effect of Derivative Financial Instruments on OCI and Net Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of (Loss) Gain Recognized in OCI on Derivative	$ (1,347)	$ 0	$ 0
Reclassification adjustment for losses realized in net income	117	0	$ 0
Amount of Gain (Loss) Recognized in Income	311	0
Interest rate products
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of (Loss) Gain Recognized in OCI on Derivative	(1,347)	0
Interest rate products \| Interest expense
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification adjustment for losses realized in net income	117	0
Interest rate products \| Other operating expenses
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Gain (Loss) Recognized in Income	(56)	0
Interest Rate lock commitments with customers \| Mortgage banking activities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Gain (Loss) Recognized in Income	570	0
Forward sale commitment \| Mortgage banking activities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Gain (Loss) Recognized in Income	$ (203)	$ 0

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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