LOANS AND THE ALLOWANCE FOR LOAN LOSSES - Allowance for loan losses by portfolio (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	$ 7,875	$ 7,451	$ 7,451
Provision for (recovery of) credit losses	367	194
Ending balance	8,242	7,645	7,875
Individually evaluated	683		833
Collectively evaluated	7,559		7,042
Loans individually evaluated	10,451		12,270
Loans collectively evaluated	1,032,027		984,289
Total Recorded Investment	1,042,478		996,559
Provision for loan losses	400	200
Cash, Securities and Other
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	1,058	764	764
Provision for (recovery of) credit losses	34	113
Ending balance	1,092	877	1,058
Collectively evaluated	1,092		1,058
Loans individually evaluated	1,493		2,803
Loans collectively evaluated	145,664		143,898
Total Recorded Investment	147,157		146,701
Construction and Development
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	200	232	232
Provision for (recovery of) credit losses	(14)	34
Ending balance	186	266	200
Collectively evaluated	186		200
Loans collectively evaluated	25,461		28,120
Total Recorded Investment	25,461		28,120
1-4 Family Residential
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	2,850	2,552	2,552
Provision for (recovery of) credit losses	158	36
Ending balance	3,008	2,588	2,850
Collectively evaluated	3,008		2,850
Loans collectively evaluated	412,306		400,134
Total Recorded Investment	412,306		400,134
Non-Owner Occupied CRE
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	1,176	1,264	1,264
Provision for (recovery of) credit losses	227	(29)
Ending balance	1,403	1,235	1,176
Collectively evaluated	1,403		1,176
Loans collectively evaluated	192,350		165,179
Total Recorded Investment	192,350		165,179
Owner Occupied CRE
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	911	789	789
Provision for (recovery of) credit losses	(27)	(9)
Ending balance	884	780	911
Collectively evaluated	884		911
Loans collectively evaluated	121,138		127,968
Total Recorded Investment	121,138		127,968
Commercial and Industrial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	1,680	1,850	1,850
Provision for (recovery of) credit losses	(11)	49
Ending balance	1,669	$ 1,899	1,680
Individually evaluated	683		833
Collectively evaluated	986		847
Loans individually evaluated	8,958		9,467
Loans collectively evaluated	135,108		118,990
Total Recorded Investment	$ 144,066		$ 128,457

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

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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