DERIVATIVE FINANCIAL INSTRUMENTS - Fair Value of Derivative Instruments (Details) $ in Thousands	Sep. 30, 2019 USD ($) instrument	Dec. 31, 2018 USD ($) instrument
Derivative [Line Items]
Notional	$ 525,711	$ 167,933
Total derivatives	566	(2,664)
Designated as Hedging Instrument
Derivative [Line Items]
Notional	75,000	75,000
Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	450,711	92,933
Total derivatives	1,157	644
Other liabilities \| Designated as Hedging Instrument
Derivative [Line Items]
Derivative Liability	(591)	$ (3,308)
Interest rate products \| Other assets \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	80,405
Derivative Asset	$ 4,085
Interest rate products \| Other liabilities \| Designated as Hedging Instrument
Derivative [Line Items]
Count \| instrument	3	3
Notional	$ 75,000	$ 75,000
Derivative Liability	(591)	(3,308)
Interest rate products \| Other liabilities \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	80,405
Derivative Liability	(5,029)
Risk participation agreements \| Other liabilities \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	5,402
Derivative Liability	(10)
Interest rate lock commitments with customers \| Other assets \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	117,744	40,795
Derivative Asset	1,940	686
Interest rate lock commitments with customers \| Other liabilities \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	23,043	6,530
Derivative Liability	(130)	(24)
Forward sale commitments \| Other assets \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	66,979	19,732
Derivative Asset	515	143
Forward sale commitments \| Other liabilities \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	76,733	25,876
Derivative Liability	$ (214)	$ (161)

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

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