Note 5 - Loans and Allowance for Loan Losses - Nonaccruing Loans (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Nonaccruing loans	$ 11,908,567	$ 9,961,517
Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Nonaccruing loans	4,329,527	4,423,074
Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Nonaccruing loans
Real Estate, Construction [Member]
Nonaccruing loans	4,270,409	4,452,409
Commercial Real Estate Portfolio Segment [Member]
Nonaccruing loans	1,551,563	161,491
Commercial Portfolio Segment [Member]
Nonaccruing loans	1,707,342	802,628
Consumer and Other Loans [Member]
Nonaccruing loans	$ 49,726	$ 121,915