Note 3 - Loans and Allowance for Credit Losses - Average Recorded Investment and Interest Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Dec. 31, 2022	Dec. 31, 2022	Jun. 30, 2023
Impaired Financing Receivable, Average Recorded Investment	$ 395	$ 410
Impaired Financing Receivable, Interest Income, Accrual Method	10	24
Impaired Financing Receivable, Interest Income, Cash Basis Method	10	10	$ 558
Commercial Portfolio Segment [Member]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	308	297
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	8	18
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	8	18
Commercial Real Estate Portfolio Segment [Member] \| Other Commercial Real Estate Loans [Member]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	40	40
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	1	4
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	1	4
Residential Portfolio Segment [Member] \| Owner Occupied Loans [Member]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	20	20
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	1	2
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	1	2
Residential Portfolio Segment [Member] \| Non-owner Occupied Loans [Member]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	27	53
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	$ 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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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-15

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+ References

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-Name Accounting Standards Codification
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+ References

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