Other Comprehensive Income - Change in Unrealized Gains and Losses on Available-for-Sale Securities (Detail) (USD $)	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Change In Unrealized Gains And Losses On Available For Sale Securities [Abstract]
Unrealized holding (losses) gains arising during the period, Before Tax Amount	$ (264,122)	$ (281,316)	$ (838,567)	$ 9,443
Reclassification adjustment for losses / net gains recognized in income, Before Tax Amount		(924,317)		(916,275)
Unrealized holding losses / gains on available for sale securities, net of taxes, Before Tax Amount	(264,122)	(1,205,633)	(838,567)	(906,832)
Unrealized holding (losses) gains arising during the period, Tax Effect		106,901		(3,590)
Reclassification adjustment for losses / net gains recognized in income, Tax Effect		351,240		348,185
Unrealized holding losses / gains on available for sale securities, net of taxes, Tax Effect		458,141		344,595
Unrealized holding (losses) gains arising during the period, Net of Tax Amount	(264,122)	(174,415)	(838,567)	5,853
Reclassification adjustment for losses / net gains recognized in income, Net of Tax Amount		(573,077)		(568,090)
Unrealized holding losses / gains on available for sale securities, net of taxes, Net of Tax Amount	$ (264,122)	$ (747,492)	$ (838,567)	$ (562,237)

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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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