Note 5 - Loans - Past Due Loans (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Loans, past due	$ 1,024,318	$ 2,392,202
Loans, current	342,916,524	333,203,714
Loans	343,940,842	335,595,916
Loans, 90 days past due and still accruing	10,507	146,459
Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due
Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	25,000
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	999,318	2,392,202
Commercial Real Estate Portfolio Segment [Member]
Loans, past due	988,811	2,245,743
Loans, current	237,845,338	231,780,831
Loans	238,834,149	234,026,574
Loans, 90 days past due and still accruing
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	988,811	2,245,743
Construction and Land Development [Member]
Loans, past due
Loans, current	18,265,505	18,160,366
Loans	18,265,505	18,160,366
Loans, 90 days past due and still accruing
Construction and Land Development [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due
Construction and Land Development [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due
Construction and Land Development [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due
Residential Portfolio Segment [Member]
Loans, past due	10,507	146,459
Loans, current	63,013,599	59,094,957
Loans	63,024,106	59,241,416
Loans, 90 days past due and still accruing	10,507	146,459
Residential Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due
Residential Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due
Residential Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	10,507	146,459
Commercial Portfolio Segment [Member]
Loans, past due	25,000
Loans, current	23,298,073	23,613,543
Loans	23,323,073	23,613,543
Loans, 90 days past due and still accruing
Commercial Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due
Commercial Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	25,000
Commercial Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due
Consumer Portfolio Segment [Member]
Loans, past due
Loans, current	494,009	554,017
Loans	494,009	554,017
Loans, 90 days past due and still accruing
Consumer Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due
Consumer Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due
Consumer Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due