DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES - Weighted Average Remaining Maturity, Lives, and Rates of Interest Rate Swaps (Details) - Interest Rate Swaps - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Financial institution counterparties | Not Designated as Hedging Instrument
Derivative [Line Items]
Notional Amount	$ 93,967	$ 67,220
Remaining Maturity	11 years 7 months 21 days	12 years 8 months 15 days
Receive Rate	2.36%	1.39%
Pay Rate	2.58%	2.37%
Financial institution counterparties | Cash Flow Hedging | Designated as Hedging Instrument
Derivative [Line Items]
Notional Amount	$ 270,000	$ 240,000
Remaining Maturity	4 years 9 months 28 days	5 years 3 months
Receive Rate	2.45%	1.44%
Pay Rate	1.58%	1.43%
Financial institution counterparties | Fair Value Hedging [Member] | Designated as Hedging Instrument
Derivative [Line Items]
Notional Amount	$ 21,100	$ 0
Remaining Maturity	7 years 6 months 1 day
Receive Rate	2.56%
Pay Rate	3.00%
Customer counterparties | Not Designated as Hedging Instrument
Derivative [Line Items]
Notional Amount	$ 93,967	$ 67,220
Remaining Maturity	11 years 7 months 21 days	12 years 8 months 15 days
Receive Rate	2.58%	2.37%
Pay Rate	2.36%	1.39%