Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Financing Receivable, Threshold Period Past Due (Day)	90 days
Mortgage Loans in Process of Foreclosure, Amount	$ 155
Interest and Fee Income, Loans and Leases, Total	34,253	$ 34,923
Financing Receivable, Troubled Debt Restructuring	$ 3,032	$ 5,878
Financing Receivable, Modifications, Number of Contracts	0	3
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0
Nonperforming Financial Instruments [Member]
Interest and Fee Income, Loans and Leases, Total	$ 0	$ 0
Commercial Real Estate Portfolio Segment [Member]
Number of Real Estate Properties	1
Commercial Real Estate Portfolio Segment [Member] \| Contractual Interest Rate Reduction [Member]
Financing Receivable, Modifications, Number of Contracts		1
Commercial Real Estate Portfolio Segment [Member] \| Re-amortization and Reduced Interest Rate [Member]
Financing Receivable, Modifications, Number of Contracts		2
Residential Portfolio Segment [Member]
Number of Real Estate Properties	0

Number of financing receivables that have been modified by troubled debt restructurings.

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Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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Threshold period for when financing receivable is considered past due, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes threshold period past due to write off as uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 14
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447

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The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.1)
-URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL49126937-111524

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The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

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