Note 3 - Loans and Allowance for Loan Losses - Nonaccruing Loans (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Nonaccruing loans	$ 9,961,517	$ 8,631,639
Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Nonaccruing loans	4,423,074	2,060,180
Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Nonaccruing loans
Real Estate, Construction [Member]
Nonaccruing loans	4,452,409	5,446,896
Commercial Real Estate Portfolio Segment [Member]
Nonaccruing loans	161,491	161,491
Commercial Portfolio Segment [Member]
Nonaccruing loans	802,628	925,281
Consumer and Other Loans [Member]
Nonaccruing loans	$ 121,915	$ 37,791