LOANS AND THE ALLOWANCE FOR LOAN LOSSES - Summary (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	$ 28,759	$ 26,087	$ 31,838	$ 22,299
Provision for loan losses	(2,162)	3,573	(5,567)	7,928
Charge-offs	(402)	(160)	(597)	(1,381)
Recoveries	312	223	833	877
Allowance for loan losses at end of period	26,507	29,723	26,507	29,723
Commercial and industrial
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	2,420	4,224	3,929	4,441
Provision for loan losses	578	125	(1,224)	663
Charge-offs	(295)		(295)	(809)
Recoveries	14	7	307	61
Allowance for loan losses at end of period	2,717	4,356	2,717	4,356
Agricultural and farmland
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	865	2,993	793	2,766
Provision for loan losses	(84)	(103)	(12)	151
Charge-offs				(27)
Allowance for loan losses at end of period	781	2,890	781	2,890
Commercial real estate - owner occupied
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	2,715	2,122	3,141	1,779
Provision for loan losses	(769)	1,135	(1,195)	1,038
Recoveries				440
Allowance for loan losses at end of period	1,946	3,257	1,946	3,257
Commercial real estate - non-owner occupied
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	11,330	4,432	11,251	3,663
Provision for loan losses	(1,511)	2,275	(1,439)	3,095
Charge-offs				(56)
Recoveries	6	60	13	65
Allowance for loan losses at end of period	9,825	6,767	9,825	6,767
Multi-family
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	2,090	1,474	1,957	1,024
Provision for loan losses	(81)	107	52	557
Allowance for loan losses at end of period	2,009	1,581	2,009	1,581
Construction and land development
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	4,006	3,223	4,232	2,977
Provision for loan losses	(261)	135	(577)	372
Charge-offs				(1)
Recoveries	179	8	269	18
Allowance for loan losses at end of period	3,924	3,366	3,924	3,366
One-to-four family residential
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	1,573	3,284	1,801	2,540
Provision for loan losses	(45)	(317)	(243)	460
Charge-offs	(41)	(8)	(113)	(112)
Recoveries	33	51	75	122
Allowance for loan losses at end of period	1,520	3,010	1,520	3,010
Municipal, consumer, and other
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	3,760	4,335	4,734	3,109
Provision for loan losses	11	216	(929)	1,592
Charge-offs	(66)	(152)	(189)	(376)
Recoveries	80	97	169	171
Allowance for loan losses at end of period	$ 3,785	$ 4,496	$ 3,785	$ 4,496

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

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- Definition

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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