LOANS AND THE ALLOWANCE FOR LOAN LOSSES - Summary (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	$ 22,299	$ 20,509	$ 19,765
Provision for loan losses	10,532	3,404	5,697
Charge-offs	(2,968)	(3,273)	(6,485)
Recoveries	1,975	1,659	1,532
Allowance for loan losses at end of period	31,838	22,299	20,509
Commercial and industrial
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	4,441	3,748	5,411
Provision for loan losses	677	1,139	(532)
Charge-offs	(1,784)	(886)	(1,446)
Recoveries	595	440	315
Allowance for loan losses at end of period	3,929	4,441	3,748
Agricultural and farmland
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	2,766	2,650	2,385
Provision for loan losses	(1,946)	146	265
Charge-offs	(27)	(30)
Allowance for loan losses at end of period	793	2,766	2,650
Commercial real estate - owner occupied
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	1,779	2,506	1,510
Provision for loan losses	961	(376)	3,294
Charge-offs	(39)	(407)	(2,352)
Recoveries	440	56	54
Allowance for loan losses at end of period	3,141	1,779	2,506
Commercial real estate - non-owner occupied
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	3,663	2,644	2,476
Provision for loan losses	7,862	1,110	264
Charge-offs	(349)	(111)	(237)
Recoveries	75	20	141
Allowance for loan losses at end of period	11,251	3,663	2,644
Multi-family
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	1,024	912	997
Provision for loan losses	933	153	109
Charge-offs		(41)	(194)
Allowance for loan losses at end of period	1,957	1,024	912
Construction and land development
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	2,977	4,176	2,981
Provision for loan losses	1,032	(1,640)	993
Charge-offs	(27)	(9)	(58)
Recoveries	250	450	260
Allowance for loan losses at end of period	4,232	2,977	4,176
One-to-four family residential
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	2,540	2,782	2,723
Provision for loan losses	(894)	513	984
Charge-offs	(155)	(1,105)	(1,415)
Recoveries	310	350	490
Allowance for loan losses at end of period	1,801	2,540	2,782
Municipal, consumer, and other
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	3,109	1,091	1,282
Provision for loan losses	1,907	2,359	320
Charge-offs	(587)	(684)	(783)
Recoveries	305	343	272
Allowance for loan losses at end of period	$ 4,734	$ 3,109	$ 1,091

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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