LOANS - By portfolio segment (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Loans
Total loans	$ 2,678,411	$ 2,646,673
Percentage of loan	100.00%	100.00%
Less allowance for credit losses for loans	$ (31,194)	$ (25,280)	$ (24,643)	$ (23,693)
Less deferred loan fees and unearned discounts	(5,942)	(6,125)
Less loans held for sale	$ (882)	$ (1,463)
Loans And Leases Receivable Allowance, Percent	100.00%	100.00%
Loans, net	$ 2,640,393	$ 2,613,805
Accrued interest receivable	7,800	7,500
Commercial and industrial
Loans
Total loans	$ 542,650	$ 527,607
Percentage of loan	20.30%	19.90%
Less allowance for credit losses for loans	$ (9,535)	$ (7,671)	(8,416)	(7,719)
Loans And Leases Receivable Allowance, Percent	30.60%	30.30%
Commercial real estate
Loans
Total loans	$ 904,395	$ 900,746
Percentage of loan	33.80%	34.00%
Less allowance for credit losses for loans	$ (9,576)	$ (7,975)	(6,784)	(6,730)
Loans And Leases Receivable Allowance, Percent	30.70%	31.60%
Construction and development
Loans
Total loans	$ 558,343	$ 527,812
Percentage of loan	20.80%	19.90%
Less allowance for credit losses for loans	$ (5,795)	$ (4,446)	(4,700)	(4,298)
Loans And Leases Receivable Allowance, Percent	18.60%	17.60%
1-4 family residential
Loans
Total loans	$ 276,142	$ 280,192
Percentage of loan	10.30%	10.60%
Less allowance for credit losses for loans	$ (2,430)	$ (2,257)	(2,249)	(2,281)
Loans And Leases Receivable Allowance, Percent	7.80%	8.90%
Multi‑family residential
Loans
Total loans	$ 267,152	$ 277,209
Percentage of loan	10.00%	10.50%
Less allowance for credit losses for loans	$ (2,413)	$ (1,699)	(1,457)	(1,511)
Loans And Leases Receivable Allowance, Percent	7.70%	6.70%
Consumer
Loans
Total loans	$ 38,133	$ 36,782
Percentage of loan	1.40%	1.40%
Less allowance for credit losses for loans	$ (477)	$ (388)	(357)	(387)
Loans And Leases Receivable Allowance, Percent	1.50%	1.50%
Agriculture
Loans
Total loans	$ 7,520	$ 9,812
Percentage of loan	0.30%	0.40%
Less allowance for credit losses for loans	$ (129)	$ (74)	(50)	(62)
Loans And Leases Receivable Allowance, Percent	0.40%	0.30%
Other
Loans
Total loans	$ 84,076	$ 86,513
Percentage of loan	3.10%	3.30%
Less allowance for credit losses for loans	$ (839)	$ (770)	$ (630)	$ (705)
Loans And Leases Receivable Allowance, Percent	2.70%	3.10%

Percentage of allowance to cover probable credit losses on loans and leases.

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Percentage of loan proportion to total loan.

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Unearned discounts (other than cash or quantity discounts and the like), finance charges, and interest included in the face amount of receivables, that are shown as a deduction from the related receivables. For example, 1) finance charges booked as a receivable when a loan is made and recognized as income at a later date; and 2) interest charges deducted from the face loan amount, resulting in a discounted amount actually advanced to the borrower (wherein the receivable includes the amount actually advanced to the borrower and the as yet unearned interest income).

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

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Amount, before allowance for credit loss, of financing receivable, classified as current.

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

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