LOANS AND THE ALLOWANCE FOR LOAN LOSSES - Allowance for loan losses by portfolio (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	$ 10,354	$ 7,575	$ 7,875	$ 7,451	$ 7,451
Provision for (recovery of) credit losses	1,496	100	3,987	216
Charge-offs	(6)		(30)
Recoveries	1		13	8
Ending balance	11,845	7,675	11,845	7,675	7,875
Individually evaluated	1,423		1,423		833
Collectively evaluated	10,422		10,422		7,042
Loans individually evaluated	9,881		9,881		12,270
Loans collectively evaluated	1,497,603		1,497,603		984,289
Total Recorded Investment	1,507,484		1,507,484		996,559
Provision for loan losses			4,000	200
Cash, Securities and Other
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	2,425	1,049	1,058	764	764
Provision for (recovery of) credit losses	192	258	1,571	535
Charge-offs	(6)		(30)
Recoveries	1		13	8
Ending balance	2,612	1,307	2,612	1,307	1,058
Individually evaluated	2		2
Collectively evaluated	2,610		2,610		1,058
Loans individually evaluated	66		66		2,803
Loans collectively evaluated	371,415		371,415		143,898
Total Recorded Investment	371,481		371,481		146,701
Construction and Development
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	484	290	200	232	232
Provision for (recovery of) credit losses	249	18	533	76
Ending balance	733	308	733	308	200
Collectively evaluated	733		733		200
Loans collectively evaluated	105,717		105,717		28,120
Total Recorded Investment	105,717		105,717		28,120
1-4 Family Residential
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	2,708	2,650	2,850	2,552	2,552
Provision for (recovery of) credit losses	392	27	250	125
Ending balance	3,100	2,677	3,100	2,677	2,850
Collectively evaluated	3,100		3,100		2,850
Loans collectively evaluated	446,959		446,959		400,134
Total Recorded Investment	446,959		446,959		400,134
Non-Owner Occupied CRE
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	1,483	1,086	1,176	1,264	1,264
Provision for (recovery of) credit losses	207	(68)	514	(246)
Ending balance	1,690	1,018	1,690	1,018	1,176
Collectively evaluated	1,690		1,690		1,176
Loans collectively evaluated	243,564		243,564		165,179
Total Recorded Investment	243,564		243,564		165,179
Owner Occupied CRE
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	760	800	911	789	789
Provision for (recovery of) credit losses	309	76	158	87
Ending balance	1,069	876	1,069	876	911
Collectively evaluated	1,069		1,069		911
Loans collectively evaluated	154,138		154,138		127,968
Total Recorded Investment	154,138		154,138		127,968
Commercial and Industrial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	2,494	1,700	1,680	1,850	1,850
Provision for (recovery of) credit losses	147	(211)	961	(361)
Ending balance	2,641	$ 1,489	2,641	$ 1,489	1,680
Individually evaluated	1,421		1,421		833
Collectively evaluated	1,220		1,220		847
Loans individually evaluated	9,815		9,815		9,467
Loans collectively evaluated	175,810		175,810		118,990
Total Recorded Investment	$ 185,625		$ 185,625		$ 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, 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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