Note 4 - Loans (Details Textual)	3 Months Ended	12 Months Ended
Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Impaired Financing Receivable, Related Allowance
Financing Receivable, Allowance for Credit Loss, Writeoff		$ 10,622	$ 702,115
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Number of Loans, Nonaccrual Status	2		2
Financing Receivable, Nonaccrual	$ 988,811		$ 988,811
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	31,733		115,168
Impaired Financing Receivable, Related Allowance
Number of Loans Classified as TDR	1		1
Financing Receivable, Troubled Debt Restructuring	$ 2,122,044		$ 2,134,570
Financing Receivable, Allowance for Credit Loss, Writeoff			690,000
Commercial Real Estate Portfolio Segment [Member] \| Nonaccrual Loans [Member]
Impaired Financing Receivable, Related Allowance	0		0
Allowance for Loan and Lease Losses Write-offs, Net, Total	690,000		$ 690,000
Residential Portfolio Segment [Member]
Impaired Financing Receivable, Related Allowance
Number of Loans Classified as TDR	1		1
Financing Receivable, Troubled Debt Restructuring	$ 52,938		$ 54,000
Financing Receivable, Allowance for Credit Loss, Writeoff
Financing Receivable, Troubled Debt Restructuring, Premodification			54,000
Commercial Real Estate and Residential Loans Classified As TDR [Member]
Financing Receivable, Allowance for Credit Loss, Writeoff	$ 0		$ 0

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

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Amount of writeoff of financing receivable, charged against allowance for credit loss.

+ References

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

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-Publisher FASB
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Amount of financing receivable on nonaccrual status.

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- Definition

Amount of allowance for credit losses related to recorded investment.

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- Definition

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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