Investment Securities - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
Jun. 30, 2014	Dec. 31, 2015	Dec. 31, 2014
Investment [Line Items]
Available for sale transferred to held to maturity, amortized cost	$ 222,322,423
Available for sale transferred to held to maturity, fair value	205,260,985
Available for sale transferred to held to maturity, net unrealized loss	$ (17,061,438)
Unamortized unrealized loss, before deferred taxes		$ 11,305,438	$ 15,516,336
Fair values of Investment securities, pledged as collateral for public deposits		201,482,967	156,226,081
Pooled Trust Preferred Securities [Member]
Investment [Line Items]
Unrealized loss on other investments		$ 15,425	$ 124,678

Available for Sale Securities Transferred to Held-To-Maturity, at Carrying Value

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- Definition

Available for Sale Securities Transferred to Held-To-Maturity, at Fair Value

+ References

No definition available.

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- Definition

Available For Sale Securities, Transferred to Held To Maturity Securities, Unrealized Gain (Loss)

+ References

No definition available.

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- Definition

Other comprehensive income loss unamortized of unrealized gain loss on transfers to held to maturity from available for sale securities before tax.

+ References

No definition available.

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- Definition

Total of all securities that are purchased with the intent to be sold in the short-term and that are pledged to one or more secured parties who have the right to buy, sell, or re-pledge the collateral.

+ References

Reference 1: 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26626-111562

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Trading Securities
-URI http://asc.fasb.org/extlink&oid=6526789

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6467456&loc=d3e113888-111728

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 6
-Article 9

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- Definition

The increase (decrease), resulting in a loss, in the difference between the fair value and the carrying value, or in the comparative fair values, of securities held at each balance sheet date, that was included in earnings for the period.

+ References

No definition available.

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