Note 4 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Recorded investment, with no related allowance recorded	$ 28,738	$ 18,695	$ 2,237
Unpaid principal balance, with no related allowance recorded	41,123	19,970	2,365
With no related allowance recorded, Average Recorded Investment	22,941	11,356	2,932
With no related allowance recorded, Interest Income Recognized	380	197	53
Recorded investment, with related allowance recorded	4,053	482	310
Unpaid principal balance, with related allowance recorded	9,782	525	347
Related allowance	564	210	141
With related allowance recorded, Average Recorded Investment	1,457	278	324
With related allowance recorded, Interest Income Recognized	24	1	0
Recorded investment	32,791	19,177	2,547
Unpaid principal balance	50,905	20,495	2,712
Average Recorded Investment	24,398	11,634	3,256
Interest Income Recognized	404	198	53
Real Estate Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	19,288	9,728	1,956
Unpaid principal balance, with no related allowance recorded	30,113	9,874	2,064
With no related allowance recorded, Average Recorded Investment	13,679	6,515	2,571
With no related allowance recorded, Interest Income Recognized	228	165	53
Related allowance	0	0	0
Recorded investment	19,288	9,728	1,956
Unpaid principal balance	30,113	9,874	2,064
Average Recorded Investment	13,679	6,515	2,571
Interest Income Recognized	228	165	53
Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Recorded investment, with no related allowance recorded	529	782	247
Unpaid principal balance, with no related allowance recorded	812	800	269
With no related allowance recorded, Average Recorded Investment	731	887	328
With no related allowance recorded, Interest Income Recognized	17	13	14
Related allowance	0	0	0
Recorded investment	529	782	247
Unpaid principal balance	812	800	269
Average Recorded Investment	731	887	328
Interest Income Recognized	17	13	14
Real Estate Portfolio Segment [Member] \| 1-4 Family [Member]
Recorded investment, with no related allowance recorded	1,995	2,280	1,662
Unpaid principal balance, with no related allowance recorded	2,081	2,353	1,745
With no related allowance recorded, Average Recorded Investment	1,965	2,172	1,507
With no related allowance recorded, Interest Income Recognized	30	26	32
Related allowance	0	0	0
Recorded investment	1,995	2,280	1,662
Unpaid principal balance	2,081	2,353	1,745
Average Recorded Investment	1,965	2,172	1,507
Interest Income Recognized	30	26	32
Real Estate Portfolio Segment [Member] \| Farmland [Member]
Recorded investment, with no related allowance recorded	79
Unpaid principal balance, with no related allowance recorded	81
With no related allowance recorded, Average Recorded Investment	193
With no related allowance recorded, Interest Income Recognized	0
Related allowance	0
Recorded investment	79
Unpaid principal balance	81
Average Recorded Investment	193
Interest Income Recognized	0
Real Estate Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Recorded investment, with no related allowance recorded	16,685	6,666	47
Unpaid principal balance, with no related allowance recorded	27,139	6,721	50
With no related allowance recorded, Average Recorded Investment	10,790	3,456	700
With no related allowance recorded, Interest Income Recognized	181	126	7
Related allowance	0	0	0
Recorded investment	16,685	6,666	47
Unpaid principal balance	27,139	6,721	50
Average Recorded Investment	10,790	3,456	700
Interest Income Recognized	181	126	7
Real Estate Portfolio Segment [Member] \| Multifamily Loans [Member]
Recorded investment, with no related allowance recorded			0
Unpaid principal balance, with no related allowance recorded			0
With no related allowance recorded, Average Recorded Investment			36
With no related allowance recorded, Interest Income Recognized			0
Related allowance			0
Recorded investment			0
Average Recorded Investment			36
Interest Income Recognized			0
Commercial Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	9,395	8,841	93
Unpaid principal balance, with no related allowance recorded	10,941	9,953	96
With no related allowance recorded, Average Recorded Investment	9,166	4,614	33
With no related allowance recorded, Interest Income Recognized	152	31	0
Recorded investment, with related allowance recorded	3,926	261
Unpaid principal balance, with related allowance recorded	9,618	260
Related allowance	468	80	0
With related allowance recorded, Average Recorded Investment	1,311	22
With related allowance recorded, Interest Income Recognized	24	0
Recorded investment	13,321	9,102	93
Unpaid principal balance	20,559	10,213	96
Average Recorded Investment	10,477	4,636	33
Interest Income Recognized	176	31	0
Consumer Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	55	126	188
Unpaid principal balance, with no related allowance recorded	69	143	205
With no related allowance recorded, Average Recorded Investment	96	227	328
With no related allowance recorded, Interest Income Recognized	0	1	0
Recorded investment, with related allowance recorded	127	221	310
Unpaid principal balance, with related allowance recorded	164	265	347
Related allowance	96	130	141
With related allowance recorded, Average Recorded Investment	146	256	324
With related allowance recorded, Interest Income Recognized	0	1	0
Recorded investment	182	347	498
Unpaid principal balance	233	408	552
Average Recorded Investment	242	483	652
Interest Income Recognized	$ 0	$ 2	$ 0

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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