Note 4 - Securities - Available-for-sale Securities by Maturity (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
1-5 years, amortized cost	$ 386,166
1-5 years, fair value	391,213
5-10 years, amortized cost	12,502,835
5-10 years, fair value	12,566,922
After 10 years, amortized cost	24,919,573
After 10 years, fair value	25,239,780
Government sponsored mortgage-backed securities and SBA loan pools not due on a single maturity date, amortized cost	56,387,276
Government sponsored mortgage-backed securities and SBA loan pools not due on a single maturity date, fair value	56,833,306
Available-for-sale securities, amortized cost	94,195,850	$ 88,102,659
Available-for-sale securities	$ 95,031,221	$ 86,266,197

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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