Note 6 - Loans and the Allowance for Loan Losses - Allowance for Credit Losses and Recorded Investment in Loans Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Mar. 01, 2022
Beginning Balance	$ 29,112	$ 22,024	$ 22,024
Charge-offs	(1,668)		(1,636)
Recoveries	184		677
Provision	1,617	3,359	8,047
Ending Balance	29,245		29,112
Allowance for credit losses, individually evaluated for impairment	386		694
Allowance for credit losses, collectively evaluated for impairment	28,859		28,418
Purchased Credit Impaired	0		0	$ 26,803
Loans receivable	3,748,498		3,189,608
Loans receivable, individually evaluated for impairment	11,286		13,821
Loans receivable, collectively evaluated for impairment	3,671,490		3,124,567
Purchased Credit Impaired	65,722		51,220
Commercial Real Estate Portfolio Segment [Member] \| Construction and Land [Member]
Beginning Balance	4,498	3,584	3,584
Charge-offs	(6)		(28)
Recoveries	1		1
Provision	(15)		941
Ending Balance	4,478		4,498
Allowance for credit losses, individually evaluated for impairment	32		26
Allowance for credit losses, collectively evaluated for impairment	4,446		4,472
Purchased Credit Impaired	0		0
Loans receivable	581,661		548,528
Loans receivable, individually evaluated for impairment	1,195		1,358
Loans receivable, collectively evaluated for impairment	579,540		546,164
Purchased Credit Impaired	926		1,006
Commercial Real Estate Portfolio Segment [Member] \| Farmland [Member]
Beginning Balance	721	600	600
Charge-offs	0		(1)
Recoveries	0		2
Provision	477		120
Ending Balance	1,198		721
Allowance for credit losses, individually evaluated for impairment	0		0
Allowance for credit losses, collectively evaluated for impairment	1,198		721
Purchased Credit Impaired	0		0
Loans receivable	149,270		87,463
Loans receivable, individually evaluated for impairment	147		74
Loans receivable, collectively evaluated for impairment	149,120		87,387
Purchased Credit Impaired	3		2
Commercial Real Estate Portfolio Segment [Member] \| Nonfarm Nonresidential [Member]
Beginning Balance	9,794	7,369	7,369
Charge-offs	0		(139)
Recoveries	3		99
Provision	785		2,465
Ending Balance	10,582		9,794
Allowance for credit losses, individually evaluated for impairment	104		83
Allowance for credit losses, collectively evaluated for impairment	10,478		9,711
Purchased Credit Impaired	0		0
Loans receivable	1,481,046		1,144,426
Loans receivable, individually evaluated for impairment	2,998		2,959
Loans receivable, collectively evaluated for impairment	1,441,331		1,118,836
Purchased Credit Impaired	36,717		22,631
Residential Portfolio Segment [Member] \| Real Estate Residential One- to Four-Family [Member]
Beginning Balance	3,791	3,453	3,453
Charge-offs	(3)		(169)
Recoveries	1		39
Provision	37		468
Ending Balance	3,826		3,791
Allowance for credit losses, individually evaluated for impairment	98		110
Allowance for credit losses, collectively evaluated for impairment	3,728		3,681
Purchased Credit Impaired	0		0
Loans receivable	485,067		467,699
Loans receivable, individually evaluated for impairment	3,523		3,627
Loans receivable, collectively evaluated for impairment	462,650		444,934
Purchased Credit Impaired	18,894		19,138
Residential Portfolio Segment [Member] \| Multi-family Residential [Member]
Beginning Balance	774	818	818
Charge-offs	0
Recoveries	0		0
Provision	42		(44)
Ending Balance	816		774
Allowance for credit losses, individually evaluated for impairment	0		0
Allowance for credit losses, collectively evaluated for impairment	816		774
Purchased Credit Impaired	0		0
Loans receivable	109,773		97,508
Loans receivable, individually evaluated for impairment	0		0
Loans receivable, collectively evaluated for impairment	109,773		97,508
Purchased Credit Impaired	0		0
Commercial Portfolio Segment [Member]
Beginning Balance	8,358	5,018	5,018
Charge-offs	(1,496)		(830)
Recoveries	125		417
Provision	239		3,753
Ending Balance	7,226		8,358
Allowance for credit losses, individually evaluated for impairment	147		438
Allowance for credit losses, collectively evaluated for impairment	7,079		7,920
Purchased Credit Impaired	0		0
Loans receivable	817,093		721,385
Loans receivable, individually evaluated for impairment	3,248		5,514
Loans receivable, collectively evaluated for impairment	805,597		708,346
Purchased Credit Impaired	8,248		7,525
Consumer Portfolio Segment [Member]
Beginning Balance	1,176	$ 1,182	1,182
Charge-offs	(163)		(469)
Recoveries	54		119
Provision	52		344
Ending Balance	1,119		1,176
Allowance for credit losses, individually evaluated for impairment	5		37
Allowance for credit losses, collectively evaluated for impairment	1,114		1,139
Purchased Credit Impaired	0		0
Loans receivable	124,588		122,599
Loans receivable, individually evaluated for impairment	175		289
Loans receivable, collectively evaluated for impairment	123,479		121,392
Purchased Credit Impaired	$ 934		$ 918

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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Reserve for loans impairments recorded after acquisition as a result of current information and events which result in it being probable that estimated cash flows will be less than previously expected or because actual cash flows are less than cash flows previously expected. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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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 before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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