Note 7 - Fair Value (Details Textual)	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	$ 319,000	$ 147,000	$ 319,000	$ 147,000	$ 458,000
Impaired Financing Receivable, Related Allowance	31,000	12,000	31,000	12,000	60,000
Provision for Loan and Lease Losses, Total	$ 250,000	1,100,000	$ 525,000	1,892,000
Measurement Input, Discount Rate [Member]
Other Real Estate Owned, Measurement Input	0.10		0.10
Fair Value, Nonrecurring [Member]
Provision for Loan and Lease Losses, Total	$ 0	32,000	$ 0	32,000
Other Real Estate, Ending Balance	0		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	1,000	7,000	1,000	31,000
Commercial Business [Member]
Impaired Financing Receivable, Unpaid Principal Balance, Total	4,000		4,000		4,000
Residential Mortgage Loan [Member]
Impaired Financing Receivable, Unpaid Principal Balance, Total	0		0
Commercial Real Estate Portfolio Segment [Member]
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	315,000	0	315,000	0	380,000
Impaired Financing Receivable, Related Allowance	27,000	0	27,000	0	40,000
Provision for Loan and Lease Losses, Total	409,000	465,000	796,000	1,071,000
Commercial Portfolio Segment [Member]
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	4,000	72,000	4,000	72,000	78,000
Impaired Financing Receivable, Related Allowance	4,000	11,000	4,000	11,000	20,000
Provision for Loan and Lease Losses, Total	63,000	$ 268,000	(3,000)	$ 313,000
Collateral Pledged [Member] \| Commercial Real Estate Portfolio Segment [Member]
Impaired Financing Receivable, with Related Allowance, Fair Value	288,000		288,000		340,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	315,000		315,000		380,000
Impaired Financing Receivable, Related Allowance	$ 27,000		$ 27,000		40,000
Collateral Pledged [Member] \| Commercial Portfolio Segment [Member]
Impaired Financing Receivable, with Related Allowance, Fair Value					58,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance					78,000
Impaired Financing Receivable, Related Allowance					$ 20,000

Fair value portion of impaired financing receivable with related allowance.

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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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Amount of expense related to estimated loss from loan and lease transactions.

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