Note 4 - Available-for-sale Securities - Carrying Amount of Securities and Fair Value (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Total, amortized cost	$ 44,104,831	$ 33,959,844
Available-for-sale securities, gross unrealized gains	671,824	118,187
Available-for-sale securities, gross unrealized losses	(259,477)	(649,373)
Available-for-sale securities, fair value	44,517,178	33,428,658
Asset-backed Securities [Member]
Total, amortized cost	30,722,958	28,799,904
Available-for-sale securities, gross unrealized gains	415,564	115,824
Available-for-sale securities, gross unrealized losses	(119,774)	(605,370)
Available-for-sale securities, fair value	31,018,748	28,310,358
US Government Agencies Debt Securities [Member]
Total, amortized cost	1,102,532	1,487,917
Available-for-sale securities, gross unrealized gains	1,739
Available-for-sale securities, gross unrealized losses	(24,824)	(42,885)
Available-for-sale securities, fair value	1,079,447	1,445,032
US States and Political Subdivisions Debt Securities [Member]
Total, amortized cost	12,279,341	3,672,023
Available-for-sale securities, gross unrealized gains	254,521	2,363
Available-for-sale securities, gross unrealized losses	(114,879)	(1,118)
Available-for-sale securities, fair value	$ 12,418,983	$ 3,673,268

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

No definition available.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

+ Details

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

+ Details

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

+ Details

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