LOANS AND THE ALLOWANCE FOR LOAN LOSSES - Summary (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	$ 26,507	$ 29,723	$ 31,838	$ 22,299
Provision for loan losses	(1,667)	2,174	(7,234)	10,102
Charge-offs	(278)	(1,078)	(875)	(2,459)
Recoveries	299	835	1,132	1,712
Allowance for loan losses at end of period	24,861	31,654	24,861	31,654
Commercial and industrial
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	2,717	4,356	3,929	4,441
Provision for loan losses	162	(98)	(1,062)	565
Charge-offs	(135)	(881)	(430)	(1,690)
Recoveries	114	517	421	578
Allowance for loan losses at end of period	2,858	3,894	2,858	3,894
Agricultural and farmland
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	781	2,890	793	2,766
Provision for loan losses	(26)	(585)	(38)	(434)
Charge-offs				(27)
Allowance for loan losses at end of period	755	2,305	755	2,305
Commercial real estate - owner occupied
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	1,946	3,257	3,141	1,779
Provision for loan losses	(395)	86	(1,590)	1,124
Charge-offs		(39)		(39)
Recoveries				440
Allowance for loan losses at end of period	1,551	3,304	1,551	3,304
Commercial real estate - non-owner occupied
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	9,825	6,767	11,251	3,663
Provision for loan losses	(710)	2,496	(2,149)	5,591
Charge-offs				(56)
Recoveries	6	5	19	70
Allowance for loan losses at end of period	9,121	9,268	9,121	9,268
Multi-family
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	2,009	1,581	1,957	1,024
Provision for loan losses	(228)	614	(176)	1,171
Allowance for loan losses at end of period	1,781	2,195	1,781	2,195
Construction and land development
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	3,924	3,366	4,232	2,977
Provision for loan losses	413	179	(164)	551
Charge-offs		(26)		(27)
Recoveries	1	198	270	216
Allowance for loan losses at end of period	4,338	3,717	4,338	3,717
One-to-four family residential
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	1,520	3,010	1,801	2,540
Provision for loan losses	(499)	138	(742)	598
Charge-offs	(48)	(42)	(161)	(154)
Recoveries	135	46	210	168
Allowance for loan losses at end of period	1,108	3,152	1,108	3,152
Municipal, consumer, and other
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	3,785	4,496	4,734	3,109
Provision for loan losses	(384)	(656)	(1,313)	936
Charge-offs	(95)	(90)	(284)	(466)
Recoveries	43	69	212	240
Allowance for loan losses at end of period	$ 3,349	$ 3,819	$ 3,349	$ 3,819

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

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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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