Securities - Amortized cost and approximate fair values, together with gross unrealized gains and losses, of securities (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, amortized cost	$ 86,275,846	$ 95,606,893
Available-for-sale securities, gross unrealized gains	1,563,287	1,957,062
Available-for-sale securities, gross unrealized losses	(365,801)	(879,058)
Available-for-sale securities, fair value	87,473,332	96,684,897
U.S. Government and federal agencies
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, amortized cost	15,979,475	10,031,683
Available-for-sale securities, gross unrealized gains	44,972	65,328
Available-for-sale securities, gross unrealized losses	(85,750)	(138,738)
Available-for-sale securities, fair value	15,938,697	9,958,273
Mortgage-backed securities (Government-sponsored enterprises - residential)
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, amortized cost	23,067,200	41,196,695
Available-for-sale securities, gross unrealized gains	211,987	433,757
Available-for-sale securities, gross unrealized losses	(100,792)	(210,531)
Available-for-sale securities, fair value	23,178,395	41,419,921
Municipal bonds
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, amortized cost	47,229,171	44,378,515
Available-for-sale securities, gross unrealized gains	1,306,328	1,457,977
Available-for-sale securities, gross unrealized losses	(179,259)	(529,789)
Available-for-sale securities, fair value	$ 48,356,240	$ 45,306,703

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=51813488&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=27724398&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=49167202&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=27724398&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=27724398&loc=d3e27161-111563

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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

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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