LOANS AND THE ALLOWANCE FOR LOAN LOSSES - Summary (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	$ 31,838	$ 22,299
Provision for loan losses	(3,405)	4,355
Charge-offs	(195)	(1,221)
Recoveries	521	654
Allowance for loan losses at end of period	28,759	26,087
Commercial and industrial
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	3,929	4,441
Provision for loan losses	(1,802)	538
Charge-offs		(809)
Recoveries	293	54
Allowance for loan losses at end of period	2,420	4,224
Agricultural and farmland
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	793	2,766
Provision for loan losses	72	254
Charge-offs		(27)
Allowance for loan losses at end of period	865	2,993
Commercial real estate - owner occupied
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	3,141	1,779
Provision for loan losses	(426)	(97)
Recoveries		440
Allowance for loan losses at end of period	2,715	2,122
Commercial real estate - non-owner occupied
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	11,251	3,663
Provision for loan losses	72	820
Charge-offs		(56)
Recoveries	7	5
Allowance for loan losses at end of period	11,330	4,432
Multi-family
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	1,957	1,024
Provision for loan losses	133	450
Allowance for loan losses at end of period	2,090	1,474
Construction and land development
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	4,232	2,977
Provision for loan losses	(316)	237
Charge-offs		(1)
Recoveries	90	10
Allowance for loan losses at end of period	4,006	3,223
One-to-four family residential
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	1,801	2,540
Provision for loan losses	(198)	777
Charge-offs	(72)	(104)
Recoveries	42	71
Allowance for loan losses at end of period	1,573	3,284
Municipal, consumer, and other
Activity in the allowance for loan losses
Allowance for loan losses at beginning of period	4,734	3,109
Provision for loan losses	(940)	1,376
Charge-offs	(123)	(224)
Recoveries	89	74
Allowance for loan losses at end of period	$ 3,760	$ 4,335

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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