Note 19 - Fair Value of Financial Instruments - Significant Unobservable Inputs (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Impaired loans, fair value disclosure	$ 5,436,972	$ 5,968,221
Commercial Real Estate Portfolio Segment [Member]
Impaired loans, fair value disclosure	3,483,078	3,718,686
One-to-four Family Residential Real Estate Portfolio Segment [Member]
Impaired loans, fair value disclosure	679,184	648,880
Commercial and Industrial Portfolio Segment [Member]
Impaired loans, fair value disclosure	1,274,710	1,600,655
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Impaired loans, fair value disclosure	5,436,972	5,968,221
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Market Approach Valuation Technique [Member] | Commercial Real Estate Portfolio Segment [Member]
Impaired loans, fair value disclosure	$ 3,483,078	$ 3,718,686
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Market Approach Valuation Technique [Member] | Commercial Real Estate Portfolio Segment [Member] | Minimum [Member]
Unobservable input valuation	17.00%	17.00%
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Market Approach Valuation Technique [Member] | Commercial Real Estate Portfolio Segment [Member] | Maximum [Member]
Unobservable input valuation	18.00%	18.00%
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Market Approach Valuation Technique [Member] | One-to-four Family Residential Real Estate Portfolio Segment [Member]
Impaired loans, fair value disclosure	$ 679,184	$ 648,880
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Market Approach Valuation Technique [Member] | One-to-four Family Residential Real Estate Portfolio Segment [Member] | Minimum [Member]
Unobservable input valuation	17.00%	17.00%
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Market Approach Valuation Technique [Member] | One-to-four Family Residential Real Estate Portfolio Segment [Member] | Maximum [Member]
Unobservable input valuation	18.00%	18.00%
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Market Approach Valuation Technique [Member] | Commercial and Industrial Portfolio Segment [Member]
Impaired loans, fair value disclosure	$ 1,274,710	$ 1,600,655
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Market Approach Valuation Technique [Member] | Commercial and Industrial Portfolio Segment [Member] | Minimum [Member]
Unobservable input valuation	17.00%	17.00%
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Market Approach Valuation Technique [Member] | Commercial and Industrial Portfolio Segment [Member] | Maximum [Member]
Unobservable input valuation	18.00%	18.00%