Note 2 - Available-for-sale Securities - Carrying Amount of Securities and Fair Value (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Total, amortized cost	$ 32,748,145	$ 33,959,844
Available-for-sale securities, gross unrealized gains	278,276	118,187
Available-for-sale securities, gross unrealized losses	(455,542)	(649,373)
Available-for-sale securities, fair value	32,570,879	33,428,658
Asset-backed Securities [Member]
Total, amortized cost	27,719,782	28,799,904
Available-for-sale securities, gross unrealized gains	232,930	115,824
Available-for-sale securities, gross unrealized losses	(409,694)	(605,370)
Available-for-sale securities, fair value	27,543,018	28,310,358
US Government Agencies Debt Securities [Member]
Total, amortized cost	1,356,271	1,487,917
Available-for-sale securities, gross unrealized gains
Available-for-sale securities, gross unrealized losses	(45,848)	(42,885)
Available-for-sale securities, fair value	1,310,423	1,445,032
US States and Political Subdivisions Debt Securities [Member]
Total, amortized cost	3,672,092	3,672,023
Available-for-sale securities, gross unrealized gains	45,346	2,363
Available-for-sale securities, gross unrealized losses		(1,118)
Available-for-sale securities, fair value	$ 3,717,438	$ 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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Balance Type:	debit
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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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