Note 5 - Loans and Allowance for Loan Losses - Nonaccruing Loans (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Nonaccruing loans	$ 11,013,176	$ 10,003,477
Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Nonaccruing loans	2,380,345	2,398,379
Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Nonaccruing loans	0	0
Real Estate, Construction [Member]
Nonaccruing loans	4,437,498	3,738,410
Commercial Real Estate Portfolio Segment [Member]
Nonaccruing loans	3,236,784	2,941,143
Commercial Portfolio Segment [Member]
Nonaccruing loans	827,644	855,761
Consumer and Other Loans [Member]
Nonaccruing loans	$ 130,905	$ 69,784