COMMITMENTS, CONTINGENCIES, AND CREDIT RISK - CREDIT RISK (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Concentration of Credit Risk
Loan portfolio	$ 1,033,681	$ 805,999
Commercial real estate
Concentration of Credit Risk
Loan portfolio	494,525	405,092
Bank \| Commercial real estate \| Commercial loan portfolio \| Credit risk concentration
Concentration of Credit Risk
Loan portfolio	$ 150,251	$ 119,025
Percentage of concentration risk under a specified benchmark	20.95%	20.77%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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