Note 4 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2022	Dec. 31, 2022
Recorded investment with no allowance	$ 1,973	$ 1,973	$ 1,780
Unpaid principal balance with no allowance	2,167	2,167	1,960
Average recorded investment with no allowance	1,861	1,853
Interest income recognized with no allowance	10	36
Recorded investment with allowance	0	0	155
Unpaid principal balance with allowance	0	0	155
Related allowance	0	0	155
Average recorded investment with allowance	157	229
Interest income recognized with allowance	0	0
Recorded investment	1,973	1,973	1,935
Unpaid principal balance	2,167	2,167	2,115
Average recorded investment	2,018	2,082
Interest income recognized	10	36
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Recorded investment with no allowance	894	894	854
Unpaid principal balance with no allowance	1,053	1,053	996
Average recorded investment with no allowance	891	903
Interest income recognized with no allowance	2	9
Recorded investment with allowance	0	0	0
Unpaid principal balance with allowance	0	0	0
Related allowance	0	0	0
Average recorded investment with allowance	15	14
Interest income recognized with allowance	0	0
Recorded investment	894	894	854
Unpaid principal balance	1,053	1,053	996
Average recorded investment	906	917
Interest income recognized	2	9
Real Estate Mortgage Portfolio Segment [Member] \| Land Loan [Member]
Recorded investment with no allowance	51	51	51
Unpaid principal balance with no allowance	51	51	51
Average recorded investment with no allowance	51	76
Interest income recognized with no allowance	0	0
Recorded investment with allowance	0	0	0
Unpaid principal balance with allowance	0	0	0
Related allowance	0	0	0
Average recorded investment with allowance	0	0
Interest income recognized with allowance	0	0
Recorded investment	51	51	51
Unpaid principal balance	51	51	51
Average recorded investment	51	76
Interest income recognized	0	0
Real Estate Mortgage Portfolio Segment [Member] \| Construction Loans [Member]
Recorded investment with no allowance	0	0	0
Unpaid principal balance with no allowance	0	0	0
Average recorded investment with no allowance	0	0
Interest income recognized with no allowance	0	0
Recorded investment with allowance	0	0	0
Unpaid principal balance with allowance	0	0	0
Related allowance	0	0	0
Average recorded investment with allowance	0	0
Interest income recognized with allowance	0	0
Recorded investment	0	0	0
Unpaid principal balance	0	0	0
Average recorded investment	0	0
Interest income recognized	0	0
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Recorded investment with no allowance	566	566	463
Unpaid principal balance with no allowance	585	585	484
Average recorded investment with no allowance	573	612
Interest income recognized with no allowance	6	20
Recorded investment with allowance	0	0	0
Unpaid principal balance with allowance	0	0	0
Related allowance	0	0	0
Average recorded investment with allowance	0	0
Interest income recognized with allowance	0	0
Recorded investment	566	566	463
Unpaid principal balance	585	585	484
Average recorded investment	573	612
Interest income recognized	6	20
Commercial Portfolio Segment [Member]
Recorded investment with no allowance	147	147	40
Unpaid principal balance with no allowance	147	147	40
Average recorded investment with no allowance	153	162
Interest income recognized with no allowance	2	7
Recorded investment with allowance	0	0	155
Unpaid principal balance with allowance	0	0	155
Related allowance	0	0	155
Average recorded investment with allowance	0	0
Interest income recognized with allowance	0	0
Recorded investment	147	147	195
Unpaid principal balance	147	147	195
Average recorded investment	153	162
Interest income recognized	2	7
Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Recorded investment with no allowance	315	315	372
Unpaid principal balance with no allowance	331	331	389
Average recorded investment with no allowance	193	100
Interest income recognized with no allowance	0	0
Recorded investment with allowance	0	0	0
Unpaid principal balance with allowance	0	0	0
Related allowance	0	0	0
Average recorded investment with allowance	142	215
Interest income recognized with allowance	0	0
Recorded investment	315	315	372
Unpaid principal balance	331	331	389
Average recorded investment	335	315
Interest income recognized	0	0
Consumer Portfolio Segment [Member] \| All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Recorded investment with no allowance	0	0	0
Unpaid principal balance with no allowance	0	0	0
Average recorded investment with no allowance	0	0
Interest income recognized with no allowance	0	0
Recorded investment with allowance	0	0	0
Unpaid principal balance with allowance	0	0	0
Related allowance	0	0	0
Average recorded investment with allowance	0	0
Interest income recognized with allowance	0	0
Recorded investment	0	0	0
Unpaid principal balance	0	0	$ 0
Average recorded investment	0	0
Interest income recognized	$ 0	$ 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
-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
-Name Accounting Standards Codification
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-Section 50
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-17

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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