Note 5 - Loans (Details Textual)	12 Months Ended
Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Financing Receivable, Allowance for Credit Losses, Recovery	$ 277,538	$ 8,261
Financing Receivable, Allowance for Credit Losses, Write-downs	702,115	322,436
Participating Mortgage Loans, Participation Liabilities, Amount	30,000,000	$ 31,700,000
Federal Home Loan Bank of Atlanta [Member]
Loans Pledged as Collateral	63,000,000
Federal Home Loan Bank of Richmond [Member]
Loans Pledged as Collateral	$ 51,000,000
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Number of Loans, Nonaccrual Status	2	1
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 988,811	$ 2,245,743
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	115,168	82,070
Impaired Financing Receivable, Related Allowance		127,213
Financing Receivable, Allowance for Credit Losses, Recovery	$ 204,660	$ 4,780
Number of Loans Classified as TDR	1	3
Financing Receivable, Modifications, Recorded Investment	$ 2,134,570	$ 2,937,439
Financing Receivable, Modifications, Pre-Modification Recorded Investment		774,274
Financing Receivable, Allowance for Credit Losses, Write-downs	690,000	275,000
Commercial Real Estate Portfolio Segment [Member] \| Nonaccrual Loans [Member]
Impaired Financing Receivable, Related Allowance	0	127,213
Allowance for Loan and Lease Losses Write-offs, Net, Total	690,000	275,000
Financing Receivable, Allowance for Credit Losses, Recovery	197,660
Residential Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses, Recovery		148
Number of Loans Classified as TDR	1
Financing Receivable, Modifications, Recorded Investment	$ 54,000
Financing Receivable, Modifications, Pre-Modification Recorded Investment	54,000
Financing Receivable, Allowance for Credit Losses, Write-downs
Commercial Real Estate and Residential Loans Classified As TDR [Member]
Financing Receivable, Allowance for Credit Losses, Write-downs	0
Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses, Recovery	9,167	3,333
Financing Receivable, Allowance for Credit Losses, Write-downs	$ 0

Represents the number of loans in financing receivables that are on nonaccrual status as of the balance sheet date.

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Represents the number of loans classified as troubled debt restructurings as of the balance sheet date.

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Amount, after recoveries, of loans and leases that have been written-off.

+ References

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of direct write-downs of financing receivables charged against the allowance.

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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Amount of allowance for credit losses related to recorded investment.

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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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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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The aggregate amount of the participation liability at the end of the accounting period.

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