DERIVATIVES - Net gain and losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Derivative [Line Items]
Loss in OCI on derivatives (effective portion), net of tax	$ (1,361)	$ 1,336	$ 1,417	$ 3,824
Total	6,179	119	7,698	681
Designated as Hedging Instrument
Derivative [Line Items]
Loss in OCI on derivatives (effective portion), net of tax	(1,269)		(1,269)
Gain reclassified from OCI into interest income or interest expense (effective portion)	149		149
Mortgage banking income \| Not designated as hedging instruments \| Derivative loan commitments
Derivative [Line Items]
Total	4,337	470	9,528	1,014
Mortgage banking income \| Not designated as hedging instruments \| Forward loan sale commitments
Derivative [Line Items]
Total	$ 1,842	$ (351)	$ (1,830)	$ (333)

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

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