Note 4 - Loans - Impaired Loan Balances by Portfolio Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Recorded investment, with no related allowance recorded	$ 5,094	$ 2,218
Unpaid principal balance, with no related allowance recorded		2,226
Average recorded investment, with no related allowance recorded	3,668	2,404
Interest income recognized, with no related allowance recorded		66
Unpaid principal balance	5,100	2,233
Related allowance	0	7
Interest income recognized	169	69
Recorded investment, with a related allowance recorded	0	14
Unpaid principal balance, with a related allowance recorded	0	7
Average recorded investment, with a related allowance recorded	218	116
Interest income recognized, with a related allowance recorded	0	3
Recorded investment	5,094	2,232
Average recorded investment	3,886	2,520
Commercial Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	0	0
Unpaid principal balance, with no related allowance recorded	0	0
Average recorded investment, with no related allowance recorded	0	4
Interest income recognized, with no related allowance recorded	0	0
Unpaid principal balance	0	7
Related allowance	0	7
Interest income recognized	0	1
Recorded investment, with a related allowance recorded	0	14
Unpaid principal balance, with a related allowance recorded	0	7
Average recorded investment, with a related allowance recorded	139	25
Interest income recognized, with a related allowance recorded	0	1
Recorded investment	0	14
Average recorded investment	139	29
Commercial Real Estate Portfolio Segment [Member] \| Construction and Land Development [Member]
Recorded investment, with no related allowance recorded	0	0
Unpaid principal balance, with no related allowance recorded	0	0
Average recorded investment, with no related allowance recorded	0	0
Interest income recognized, with no related allowance recorded	0	0
Unpaid principal balance	0	0
Related allowance	0	0
Interest income recognized	0	0
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	0	0
Average recorded investment	0	0
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Commercial Real Estate [Member]
Recorded investment, with no related allowance recorded	2,420	8
Unpaid principal balance, with no related allowance recorded	2,420	5
Average recorded investment, with no related allowance recorded	1,454	71
Interest income recognized, with no related allowance recorded	108	1
Unpaid principal balance	2,420	5
Related allowance	0	0
Interest income recognized	108	1
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	2,420	8
Average recorded investment	1,454	71
Commercial Real Estate Portfolio Segment [Member] \| Non-owner Occupied Commercial Real Estate [Member]
Recorded investment, with no related allowance recorded	1,360	1,185
Unpaid principal balance, with no related allowance recorded	1,359	1,186
Average recorded investment, with no related allowance recorded	1,186	1,107
Interest income recognized, with no related allowance recorded	40	23
Unpaid principal balance	1,359	1,186
Related allowance	0	0
Interest income recognized	40	23
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Average recorded investment, with a related allowance recorded	0	30
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	1,360	1,185
Average recorded investment	1,186	1,137
Residential Portfolio Segment [Member] \| Residential [Member]
Recorded investment, with no related allowance recorded	1,149	1,021
Unpaid principal balance, with no related allowance recorded	1,156	1,031
Average recorded investment, with no related allowance recorded	935	1,217
Interest income recognized, with no related allowance recorded	21	41
Unpaid principal balance	1,156	1,031
Related allowance	0	0
Interest income recognized	21	43
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Average recorded investment, with a related allowance recorded	41	61
Interest income recognized, with a related allowance recorded	0	2
Recorded investment	1,149	1,021
Average recorded investment	976	1,278
Residential Portfolio Segment [Member] \| Home Equity Line of Credit [Member]
Recorded investment, with no related allowance recorded	165	4
Unpaid principal balance, with no related allowance recorded	165	4
Average recorded investment, with no related allowance recorded	93	5
Interest income recognized, with no related allowance recorded	0	1
Unpaid principal balance	165	4
Related allowance	0	0
Interest income recognized	0	1
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	165	4
Average recorded investment	93	5
Consumer Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	0	0
Unpaid principal balance, with no related allowance recorded	0	0
Average recorded investment, with no related allowance recorded	0	0
Interest income recognized, with no related allowance recorded	0	0
Unpaid principal balance	0	0
Related allowance	0	0
Interest income recognized	0	0
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Average recorded investment, with a related allowance recorded	38	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	0	0
Average recorded investment	$ 38	$ 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
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-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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