Note 5 - Loans and Allowance for Loan Losses - Nonaccruing Loans (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Nonaccruing loans	$ 11,143,135	$ 10,003,477
Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Nonaccruing loans	2,136,793	2,398,379
Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Nonaccruing loans
Real Estate, Construction [Member]
Nonaccruing loans	4,423,691	3,738,410
Commercial Real Estate Portfolio Segment [Member]
Nonaccruing loans	3,292,149	2,941,143
Commercial Portfolio Segment [Member]
Nonaccruing loans	1,103,678	855,761
Consumer and Other Loans [Member]
Nonaccruing loans	$ 186,824	$ 69,784