Note 4 - Loans (Details Textual)	12 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Loan Balance For Reviewing High Risk Loans Minimum	$ 250,000
Impaired Financing Receivable, Interest Income, Accrual Method, Total	175,000	$ 320,000
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	221,000	226,000
Impaired Financing Receivable, Recorded Investment, Total	23,955,000	24,473,000
Impaired Financing Receivable, Related Allowance	3,155,000	$ 1,418,000
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	$ 0
Financing Receivable, Modifications, Number of Contracts	0	1
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down		$ 402,000
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	1	1
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 859,000	$ 131,000
Financial Asset Acquired with Credit Deterioration [Member]
Impaired Financing Receivable, Recorded Investment, Total	147,000	0
Impaired Financing Receivable, Related Allowance	$ 6,000	$ 0

Minimum loan balance for reviewing.

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

+ References

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

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

+ References

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Reflects the amount of the write-down related to a troubled debt restructuring.

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Amount of allowance for credit losses related to recorded investment.

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Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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