COMMITMENTS, CONTINGENCIES, AND CREDIT RISK - CREDIT RISK (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Concentration of Credit Risk
Loan portfolio	$ 1,054,634	$ 1,033,681	$ 988,622
Commercial real estate
Concentration of Credit Risk
Loan portfolio	507,120		$ 474,303
Bank \| Commercial real estate \| Commercial loan portfolio \| Credit risk concentration
Concentration of Credit Risk
Loan portfolio	$ 142,176	$ 150,251
Percentage of concentration risk under a specified benchmark	18.89%	20.95%

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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