Note 3 - Securities - Available-for-sale Securities (Details) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Equity Securities [Member]
Available-for-sale securities, amortized cost	$ 102,212	$ 102,212
Available-for-sale securities, gross unrealized gains	8,883	10,081
Available-for-sale securities, gross unrealized (losses)	(17,176)	(12,776)
Available-for-sale securities, approximate fair value	93,919	99,517
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized cost	39,461,752	31,132,635
Available-for-sale securities, gross unrealized gains	818,344	302,335
Available-for-sale securities, gross unrealized (losses)	(42,386)	(85,808)
Available-for-sale securities, approximate fair value	40,237,710	31,349,162
US Government Agencies Debt Securities [Member]
Available-for-sale securities, amortized cost		8,533,885
Available-for-sale securities, gross unrealized gains
Available-for-sale securities, gross unrealized (losses)		(137,101)
Available-for-sale securities, approximate fair value		8,396,784
Corporate Debt Securities [Member]
Available-for-sale securities, amortized cost	5,994,436	3,965,719
Available-for-sale securities, gross unrealized gains	60,880
Available-for-sale securities, gross unrealized (losses)	(88,091)	(152,019)
Available-for-sale securities, approximate fair value	5,967,225	3,813,700
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale securities, amortized cost	50,081,162	54,643,681
Available-for-sale securities, gross unrealized gains	318,725	13,764
Available-for-sale securities, gross unrealized (losses)	(125,695)	(1,024,121)
Available-for-sale securities, approximate fair value	50,274,192	53,633,324
Available-for-sale securities, amortized cost	95,639,562	98,378,132
Available-for-sale securities, gross unrealized gains	1,206,832	326,180
Available-for-sale securities, gross unrealized (losses)	(273,348)	(1,411,825)
Available-for-sale securities, approximate fair value	$ 96,573,046	$ 97,292,487

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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