Note 7 - Fair Value - Summarizes Financial Assets Measured at Fair Value (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Fair value, available for sale	$ 30,601,771	$ 26,591,991
Equity security at fair value	514,717	503,827
Mutual fund	514,717	503,827
Fair Value, Recurring [Member]
Fair value, available for sale	30,601,771	26,591,991
Equity security at fair value	514,717
Mutual fund	514,717
Fair Value, Nonrecurring [Member]
Other real estate owned	210,150	210,150
Impaired loans	3,163,793	3,177,381
Fair Value, Inputs, Level 1 [Member]
Equity security at fair value		503,827
Mutual fund		503,827
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Fair value, available for sale
Equity security at fair value	514,717
Mutual fund	514,717
Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Other real estate owned
Impaired loans
Fair Value, Inputs, Level 2 [Member]
Equity security at fair value
Mutual fund
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Fair value, available for sale	30,601,771	26,591,991
Equity security at fair value
Mutual fund
Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Other real estate owned
Impaired loans
Fair Value, Inputs, Level 3 [Member]
Equity security at fair value
Mutual fund
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Fair value, available for sale
Equity security at fair value
Mutual fund
Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Other real estate owned	210,150	210,150
Impaired loans	3,163,793	3,177,381
US States and Political Subdivisions Debt Securities [Member]
Fair value, available for sale	1,133,290	1,506,505
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member]
Fair value, available for sale	1,133,290	1,506,505
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Fair value, available for sale
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Fair value, available for sale	1,133,290	1,506,505
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Fair value, available for sale
SBA Pools [Member]
Fair value, available for sale	2,604,110	2,719,372
SBA Pools [Member] | Fair Value, Recurring [Member]
Fair value, available for sale	2,604,110	2,719,372
SBA Pools [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Fair value, available for sale
SBA Pools [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Fair value, available for sale	2,604,110	2,719,372
SBA Pools [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Fair value, available for sale
Collateralized Mortgage Backed Securities [Member]
Fair value, available for sale	26,864,371	22,366,114
Collateralized Mortgage Backed Securities [Member] | Fair Value, Recurring [Member]
Fair value, available for sale	26,864,371	22,366,114
Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Fair value, available for sale
Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Fair value, available for sale	26,864,371	22,366,114
Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Fair value, available for sale