Note 2 - Available-for-sale Securities - Carrying Amount of Securities and Fair Value (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Total, amortized cost	$ 30,031,711	$ 24,707,857
Available-for-sale securities, gross unrealized gains	2,380	15,385
Available-for-sale securities, gross unrealized losses	(800,715)	(323,361)
Available-for-sale securities, fair value	29,233,376	24,399,881
Asset-backed Securities [Member]
Total, amortized cost	25,445,706	21,028,794
Available-for-sale securities, gross unrealized gains	2,380	12,757
Available-for-sale securities, gross unrealized losses	(724,992)	(272,959)
Available-for-sale securities, fair value	24,723,094	20,768,592
US Government Agencies Debt Securities [Member]
Total, amortized cost	1,755,230	2,006,786
Available-for-sale securities, gross unrealized gains		44
Available-for-sale securities, gross unrealized losses	(74,124)	(49,047)
Available-for-sale securities, fair value	1,681,106	1,957,783
US States and Political Subdivisions Debt Securities [Member]
Total, amortized cost	2,830,775	1,672,277
Available-for-sale securities, gross unrealized gains		2,584
Available-for-sale securities, gross unrealized losses	(1,599)	(1,355)
Available-for-sale securities, fair value	$ 2,829,176	$ 1,673,506

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=82897076&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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