ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY OF FINANCING RECEIVABLES - Allowances Of Loan Losses And Loans Receivable By Class Disaggregated (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses	$ 10,867	$ 10,267	$ 9,190	$ 8,775
Balance Loans Individually Evaluated for Impairment	371	716
Balance Related to Loans Collectively Evaluated for Impairment	10,264	9,060
Net loans receivable	1,686,432	1,630,112
Individually Evaluated for Impairment	13,181	14,263
Collectively Evaluated for Impairment	1,673,251	1,615,849
Commercial and Industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses	920	1,175	647	603
Balance Loans Individually Evaluated for Impairment	10	353
Balance Related to Loans Collectively Evaluated for Impairment	910	822
Net loans receivable	133,654	124,937
Individually Evaluated for Impairment	309	835
Collectively Evaluated for Impairment	133,345	124,102
Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses	880	537	359	663
Balance Loans Individually Evaluated for Impairment	0	0
Balance Related to Loans Collectively Evaluated for Impairment	880	537
Net loans receivable	114,734	125,291
Individually Evaluated for Impairment	0	250
Collectively Evaluated for Impairment	114,734	125,041
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses	7,341	6,717	6,304	5,575
Balance Loans Individually Evaluated for Impairment	291	296
Balance Related to Loans Collectively Evaluated for Impairment	7,050	6,421
Net loans receivable	1,056,745	995,220
Individually Evaluated for Impairment	7,913	7,176
Collectively Evaluated for Impairment	1,048,832	988,044
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses	1,482	1,338	1,349	1,371
Balance Loans Individually Evaluated for Impairment	70	67
Balance Related to Loans Collectively Evaluated for Impairment	1,412	1,271
Net loans receivable	379,396	382,567
Individually Evaluated for Impairment	4,959	6,002
Collectively Evaluated for Impairment	374,437	376,565
Consumer and Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses	12	9	19	23
Balance Loans Individually Evaluated for Impairment	0	0
Balance Related to Loans Collectively Evaluated for Impairment	12	9
Net loans receivable	1,903	2,097
Individually Evaluated for Impairment	0	0
Collectively Evaluated for Impairment	1,903	2,097
Unallocated
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses	232	491	$ 512	$ 540
Net loans receivable	$ 0	$ 0

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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