Note 15 - Fair Values of Financial Instruments (Details Textual)	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	$ 877,000	$ 458,000
Impaired Financing Receivable, Related Allowance	285,000	60,000
Provision for Loan and Lease Losses, Total	1,066,000	3,247,000
Standby Letters of Credit	$ 444,000	493,000
Measurement Input, Discount Rate [Member]
Other Real Estate Owned, Measurement Input	0.10
Fair Value, Nonrecurring [Member]
Other Real Estate, Ending Balance	$ 0	9,000
Other Real Estate, Gross Amount		18,000
Other Real Estate, Disposals		9,000
Impaired Loans [Member]
Provision for Loan and Lease Losses, Total	267,000	81,000
Commercial Business [Member]
Impaired Financing Receivable, Unpaid Principal Balance, Total	3,000	14,000
Residential Mortgage Loan [Member]
Impaired Financing Receivable, Unpaid Principal Balance, Total	69,000
Commercial Real Estate Portfolio Segment [Member]
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	559,000	380,000
Impaired Financing Receivable, Related Allowance	88,000	40,000
Provision for Loan and Lease Losses, Total	1,186,000	2,250,000
Commercial Portfolio Segment [Member]
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	250,000	78,000
Impaired Financing Receivable, Related Allowance	196,000	20,000
Collateral Pledged [Member] \| Commercial Real Estate Portfolio Segment [Member]
Impaired Financing Receivable, with Related Allowance, Fair Value	470,000	340,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	558,000	380,000
Impaired Financing Receivable, Related Allowance	88,000	40,000
Collateral Pledged [Member] \| Commercial Portfolio Segment [Member]
Impaired Financing Receivable, with Related Allowance, Fair Value	54,000	58,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	247,000	78,000
Impaired Financing Receivable, Related Allowance	$ 193,000	$ 20,000

Fair value portion of impaired financing receivable with related allowance.

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- Definition

The gross amount of other real estate.

+ References

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An irrevocable undertaking (typically by a financial institution) to guarantee payment of a specified financial obligation.

+ References

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Amount of allowance for credit losses related to recorded investment.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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Amount of expense related to estimated loss from loan and lease transactions.

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