Note 3 - Securities - Available-for-sale Securities by Maturity (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
1-5 years, amortized cost	$ 428,963
1-5 years, fair value	430,802
5-10 years, amortized cost	11,905,343
5-10 years, fair value	11,738,780
After 10 years, amortized cost	25,136,342
After 10 years, fair value	24,619,865
Government sponsored mortgage-backed securities and SBA loan pools not due on a single maturity date, amortized cost	50,632,011
Government sponsored mortgage-backed securities and SBA loan pools not due on a single maturity date, fair value	49,476,750
Available-for-sale securities, amortized cost	88,102,659	$ 82,323,052
Available-for-sale securities	$ 86,266,197	$ 81,478,673

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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