Note 2 - Securities - Available-for-sale Securities (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Available-for-sale securities, amortized cost	$ 94,477,285	$ 98,378,132
Available-for-sale securities, gross unrealized gains	139,155	326,180
Available-for-sale securities, gross unrealized (losses)	(2,217,205)	(1,411,825)
Available-for-sale securities, approximate fair value	92,399,235	97,292,487
Equity Securities [Member]
Available-for-sale securities, amortized cost		102,212
Available-for-sale securities, gross unrealized gains		10,081
Available-for-sale securities, gross unrealized (losses)		(12,776)
Available-for-sale securities, approximate fair value		99,517
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized cost	39,357,506	31,132,635
Available-for-sale securities, gross unrealized gains	65,673	302,335
Available-for-sale securities, gross unrealized (losses)	(1,085,654)	(85,808)
Available-for-sale securities, approximate fair value	38,337,525	31,349,162
Corporate Debt Securities [Member]
Available-for-sale securities, amortized cost	7,003,986	3,965,719
Available-for-sale securities, gross unrealized gains	54,050
Available-for-sale securities, gross unrealized (losses)	(4,514)	(152,019)
Available-for-sale securities, approximate fair value	7,053,522	3,813,700
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
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale securities, amortized cost	48,115,793	54,643,681
Available-for-sale securities, gross unrealized gains	19,432	13,764
Available-for-sale securities, gross unrealized (losses)	(1,127,037)	(1,024,121)
Available-for-sale securities, approximate fair value	$ 47,008,188	$ 53,633,324

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
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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