DERIVATIVE FINANCIAL INSTRUMENTS - Fair Value of Derivative Instruments (Details) $ in Thousands	Mar. 31, 2020 USD ($) instrument	Dec. 31, 2019 USD ($) instrument
Derivative [Line Items]
Notional	$ 734,909	$ 502,172
Total derivatives	3,039	966
Designated as Hedging Instrument
Derivative [Line Items]
Notional	75,000	75,000
Total derivatives	1,300
Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	659,909	427,172
Total derivatives	1,712	1,725
Other assets \| Designated as Hedging Instrument
Derivative [Line Items]
Derivative Asset	$ 1,327
Other liabilities \| Designated as Hedging Instrument
Derivative [Line Items]
Derivative Liability		(759)
Interest rate products \| Other assets \| Designated as Hedging Instrument
Derivative [Line Items]
Count \| instrument	3
Notional	$ 75,000
Derivative Asset	1,327
Interest rate products \| Other assets \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	71,258	71,804
Derivative Asset	6,783	$ 2,520
Interest rate products \| Other liabilities \| Designated as Hedging Instrument
Derivative [Line Items]
Count \| instrument		3
Notional		$ 75,000
Derivative Liability		(759)
Interest rate products \| Other liabilities \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	71,258	71,804
Derivative Liability	(7,216)	(2,688)
Risk participation agreements \| Other liabilities \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	4,487	4,524
Derivative Liability	(13)	(4)
Interest rate lock commitments with customers \| Other assets \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	184,693	99,057
Derivative Asset	4,050	1,768
Interest rate lock commitments with customers \| Other liabilities \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	76,901	28,505
Derivative Liability	(382)	(191)
Forward sale commitments \| Other assets \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	103,222	61,301
Derivative Asset	1,531	596
Forward sale commitments \| Other liabilities \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	148,090	90,177
Derivative Liability	$ (3,041)	$ (276)

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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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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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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The number of derivative instruments of a particular group held by the entity.

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