Note 4 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Dec. 31, 2022
Recorded investment with no allowance	$ 1,664	$ 1,780
Unpaid principal balance with no allowance	1,812	1,960
Average recorded investment with no allowance	1,847
Interest income recognized	13
Recorded investment with allowance	315	155
Unpaid principal balance with allowance	325	155
Related allowance	6	155
Average recorded investment with allowance	302
Interest income recognized with allowance	0
Recorded investment	1,979	1,935
Unpaid principal balance	2,137	2,115
Average recorded investment	2,149
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Recorded investment with no allowance	796	854
Unpaid principal balance with no allowance	926	996
Average recorded investment with no allowance	915
Interest income recognized with no allowance	5
Interest income recognized	5
Recorded investment with allowance	28	0
Unpaid principal balance with allowance	28	0
Related allowance	1	0
Average recorded investment with allowance	14
Interest income recognized with allowance	0
Recorded investment	824	854
Unpaid principal balance	954	996
Average recorded investment	929
Real Estate Mortgage Portfolio Segment [Member] \| Land Loan [Member]
Recorded investment with no allowance	102	51
Unpaid principal balance with no allowance	104	51
Average recorded investment with no allowance	102
Interest income recognized with no allowance	0
Interest income recognized	0
Recorded investment with allowance	0	0
Unpaid principal balance with allowance	0	0
Related allowance		0
Average recorded investment with allowance	0
Interest income recognized with allowance	0
Recorded investment	102	51
Unpaid principal balance	104	51
Average recorded investment	102
Real Estate Mortgage Portfolio Segment [Member] \| Construction Loans [Member]
Recorded investment with no allowance	0	0
Unpaid principal balance with no allowance	0	0
Average recorded investment with no allowance	0
Interest income recognized with no allowance	0
Interest income recognized	0
Recorded investment with allowance	0	0
Unpaid principal balance with allowance	0	0
Related allowance		0
Average recorded investment with allowance	0
Interest income recognized with allowance	0
Recorded investment	0	0
Unpaid principal balance	0	0
Average recorded investment	0
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Recorded investment with no allowance	599	463
Unpaid principal balance with no allowance	616	484
Average recorded investment with no allowance	651
Interest income recognized with no allowance	6
Interest income recognized	6
Recorded investment with allowance	0	0
Unpaid principal balance with allowance	0	0
Related allowance		0
Average recorded investment with allowance	0
Interest income recognized with allowance	0
Recorded investment	599	463
Unpaid principal balance	616	484
Average recorded investment	651
Commercial Portfolio Segment [Member]
Recorded investment with no allowance	167	40
Unpaid principal balance with no allowance	166	40
Average recorded investment with no allowance	171
Interest income recognized with no allowance	2
Interest income recognized	2
Recorded investment with allowance	0	155
Unpaid principal balance with allowance	0	155
Related allowance		155
Average recorded investment with allowance	0
Interest income recognized with allowance	0
Recorded investment	167	195
Unpaid principal balance	166	195
Average recorded investment	171
Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Recorded investment with no allowance	0	372
Unpaid principal balance with no allowance	0	389
Average recorded investment with no allowance	8
Interest income recognized with no allowance	0
Interest income recognized	0
Recorded investment with allowance	287	0
Unpaid principal balance with allowance	297	0
Related allowance	5	0
Average recorded investment with allowance	288
Interest income recognized with allowance	0
Recorded investment	287	372
Unpaid principal balance	297	389
Average recorded investment	296
Consumer Portfolio Segment [Member] \| All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Recorded investment with no allowance	0	0
Unpaid principal balance with no allowance	0	0
Average recorded investment with no allowance	0
Interest income recognized with no allowance	0
Interest income recognized	0
Recorded investment with allowance	0	0
Unpaid principal balance with allowance	0	0
Related allowance		0
Average recorded investment with allowance	0
Interest income recognized with allowance	0
Recorded investment	0	0
Unpaid principal balance	0	$ 0
Average recorded investment	$ 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
-Topic 310
-SubTopic 10
-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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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