Note 2 - Investment Securities - Amortized Cost and Fair Value of Investment Securities (Details) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
US States and Political Subdivisions Debt Securities [Member]
Securities held to maturity, at amortized cost	$ 305,690,174	$ 252,624,159
Securities held to maturity, gross unrealized gains	5,533,151	3,190,558
Securities held to maturity, gross unrealized (losses)	(778,982)	(1,173,432)
HTM	310,444,343	254,641,285
Securities available for sale, amortized cost	53,887,898	26,764,981
Securities available for sale, gross unrealized gains	816,063	872,985
Securities available for sale, gross unrealized (losses)	(63,499)	(59,378)
AFS	54,640,462	27,578,588
Other Securities [Member]
Securities held to maturity, at amortized cost	1,050,000	1,050,000
Securities held to maturity, gross unrealized gains
Securities held to maturity, gross unrealized (losses)
HTM	1,050,000	1,050,000
Securities available for sale, amortized cost	2,002,113	1,108,124
Securities available for sale, gross unrealized gains	492,980	540,919
Securities available for sale, gross unrealized (losses)	(3,227)	(163)
AFS	2,491,866	1,648,880
US Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	66,966,328	216,281,416
Securities available for sale, gross unrealized gains	992,084	104,524
Securities available for sale, gross unrealized (losses)	(73,463)	(2,848,561)
AFS	67,884,949	213,537,379
Residential Mortgage Backed Securities [Member]
Securities available for sale, amortized cost	131,496,011	81,442,479
Securities available for sale, gross unrealized gains	1,824,345	511,095
Securities available for sale, gross unrealized (losses)	(147,552)	(1,283,439)
AFS	133,172,804	80,670,135
Securities held to maturity, at amortized cost	306,740,174	253,674,159
Securities held to maturity, gross unrealized gains	5,533,151	3,190,558
Securities held to maturity, gross unrealized (losses)	(778,982)	(1,173,432)
HTM	311,494,343	255,691,285
Securities available for sale, amortized cost	254,352,350	325,597,000
Securities available for sale, gross unrealized gains	4,125,472	2,029,523
Securities available for sale, gross unrealized (losses)	(287,741)	(4,191,541)
AFS	$ 258,190,081	$ 323,434,982

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)
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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)
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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

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Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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-Publisher FASB
-Name Accounting Standards Codification
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