Note 3 - Available-for-sale Securities - Scheduled Maturities (Details) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Due in one year or less, amortized cost	$ 11,294,706
Due in one year or less, fair value	11,341,059
Due after one to five years, amortized cost	27,764,508	27,151,751
Due after one to five years, fair value	28,807,095	27,510,536
Due after five to ten years, amortized cost	17,420,852	14,048,273
Due after five to ten years, fair value	18,162,759	14,163,270
Due after ten years, amortized cost	5,103,203	2,904,807
Due after ten years, fair value	5,257,368	2,843,372
Totals	61,583,269	44,104,831
Total, fair value	$ 63,568,281	$ 44,517,178

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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