Note 3 - Available-for-sale Securities - Carrying Amount of Securities and Fair Value (Details) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Totals	$ 61,583,269	$ 44,104,831
Available-for-sale securities, gross unrealized gains	1,988,222	671,824
Available-for-sale securities, gross unrealized losses	(3,210)	(259,477)
Available-for-sale securities, fair value	63,568,281	44,517,178
Asset-backed Securities [Member]
Totals	30,847,669	30,722,958
Available-for-sale securities, gross unrealized gains	1,042,749	415,564
Available-for-sale securities, gross unrealized losses	(1,391)	(119,774)
Available-for-sale securities, fair value	31,889,027	31,018,748
US Government Agencies Debt Securities [Member]
Totals	919,509	1,102,532
Available-for-sale securities, gross unrealized gains	6,596	1,739
Available-for-sale securities, gross unrealized losses	(1,819)	(24,824)
Available-for-sale securities, fair value	924,286	1,079,447
US States and Political Subdivisions Debt Securities [Member]
Totals	29,816,091	12,279,341
Available-for-sale securities, gross unrealized gains	938,877	254,521
Available-for-sale securities, gross unrealized losses		(114,879)
Available-for-sale securities, fair value	$ 30,754,968	$ 12,418,983

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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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