Note 4 - Loans - Impaired Loans (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)
Unpaid Principal Balance	$ 3,547
Investment with no allowance	1,211
Recorded investment with allowance	2,066
Recorded Investment	3,277
Related allowance	116
Average recorded investment	2,807
Real Estate Portfolio Segment [Member]
Unpaid Principal Balance	3,243
Investment with no allowance	1,015
Recorded investment with allowance	2,066
Recorded Investment	3,081
Related allowance	116
Average recorded investment	2,593
Real Estate Portfolio Segment [Member] \| Land Development And Construction Loans [Member]
Unpaid Principal Balance	0
Investment with no allowance	0
Recorded investment with allowance	0
Recorded Investment	0
Related allowance	0
Average recorded investment	86
Real Estate Portfolio Segment [Member] \| Farmland Loan [Member]
Unpaid Principal Balance	30
Investment with no allowance	30
Recorded investment with allowance	0
Recorded Investment	30
Related allowance	0
Average recorded investment	32
Real Estate Portfolio Segment [Member] \| Family Mortgages 1-4 [Member]
Unpaid Principal Balance	190
Investment with no allowance	190
Recorded investment with allowance	0
Recorded Investment	190
Related allowance	0
Average recorded investment	479
Real Estate Portfolio Segment [Member] \| Commercial Real Estate Portfolio Segment [Member]
Unpaid Principal Balance	3,023
Investment with no allowance	795
Recorded investment with allowance	2,066
Recorded Investment	2,861
Related allowance	116
Average recorded investment	1,996
Commercial Portfolio Segment [Member]
Unpaid Principal Balance	304
Investment with no allowance	196
Recorded investment with allowance	0
Recorded Investment	196
Related allowance	0
Average recorded investment	214
Commercial Portfolio Segment [Member] \| Commercial and Industrial Loans [Member]
Unpaid Principal Balance	304
Investment with no allowance	196
Recorded investment with allowance	0
Recorded Investment	196
Related allowance	0
Average recorded investment	$ 214

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
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-15

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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-Subparagraph (b)
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