Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details Textual) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Financing Receivable, Threshold Period Past Due (Day)		90 days
Mortgage Loans in Process of Foreclosure, Amount		$ 62
Interest and Fee Income, Loans and Leases, Total		34,923	$ 34,523
Financing Receivable, Troubled Debt Restructuring		$ 5,878	$ 4,249
Financing Receivable, Modifications, Number of Contracts		3	0
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
Real Estate Construction Portfolio Segment[Member]
Number of Real Estate Properties		0
Commercial Real Estate Portfolio Segment [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

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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-Section 50
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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 http://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
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-URI http://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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
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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.

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

+ References

No definition available.

+ Details

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