COMMITMENTS AND CONTINGENCIES - Contract or notional amount of exposure to off-balance-sheet risk (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Commitments to extend credit
Other Commitments [Line Items]
Contract and notional amounts of commitments	$ 721,098	$ 680,307
Financial standby letters of credit
Other Commitments [Line Items]
Contract and notional amounts of commitments	8,571	8,783
Performance standby letters of credit
Other Commitments [Line Items]
Contract and notional amounts of commitments	$ 7,094	$ 9,080