Note 7 - Fair Value (Details Textual)	3 Months Ended
Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	$ 506,000	$ 270,000	$ 458,000
Impaired Financing Receivable, Related Allowance	40,000	26,000	60,000
Provision for Loan and Lease Losses, Total	$ 275,000	792,000
Measurement Input, Discount Rate [Member]
Other Real Estate Owned, Measurement Input	0.1
Fair Value, Nonrecurring [Member]
Provision for Loan and Lease Losses, Total	$ 0	0
Other Real Estate, Ending Balance	9,000		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	1,000	24,000
Commercial Business [Member]
Impaired Financing Receivable, Unpaid Principal Balance, Total	4,000		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	373,000	150,000	380,000
Impaired Financing Receivable, Related Allowance	33,000	19,000	40,000
Provision for Loan and Lease Losses, Total	386,000	606,000
Commercial Portfolio Segment [Member]
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	64,000	45,000	78,000
Impaired Financing Receivable, Related Allowance	6,000	5,000	20,000
Provision for Loan and Lease Losses, Total	(65,000)	$ 45,000
Collateral Pledged [Member] \| Commercial Real Estate Portfolio Segment [Member]
Impaired Financing Receivable, with Related Allowance, Fair Value	339,000		340,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	372,000		380,000
Impaired Financing Receivable, Related Allowance	33,000		40,000
Collateral Pledged [Member] \| Commercial Portfolio Segment [Member]
Impaired Financing Receivable, with Related Allowance, Fair Value	58,000		58,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	60,000		78,000
Impaired Financing Receivable, Related Allowance	$ 2,000		$ 20,000

Fair value portion of impaired financing receivable with related allowance.

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- Definition

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+ References

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+ References

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-Publisher FASB
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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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+ References

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

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