Other Comprehensive Income - Change in Unrealized Gains and Losses on Available-for-Sale Securities (Detail) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Change In Unrealized Gains And Losses On Available For Sale Securities [Abstract]
Unrealized holding gains (losses) arising during the period, Before Tax Amount	$ (629,406)	$ 198,155	$ (574,445)	$ 306,842
Reclassification adjustment for losses recognized in income, Before Tax Amount				(8,042)
Unrealized holding gains (losses) on available for sale securities, net of taxes, Before Tax Amount	(629,406)	198,155	(574,445)	298,800
Unrealized holding gains (losses) arising during the period, Tax Effect		(75,299)		(116,601)
Reclassification adjustment for losses recognized in income, Tax Effect				3,056
Unrealized holding gains (losses) on available for sale securities, net of taxes, Tax Effect		(75,299)		(113,545)
Unrealized holding gains (losses) arising during the period, Net of Tax Amount	(629,406)	122,856	(574,445)	190,241
Reclassification adjustment for losses recognized in income, Net of Tax Amount				(4,986)
Unrealized holding gains (losses) on available for sale securities, net of taxes, Net of Tax Amount	$ (629,406)	$ 122,856	$ (574,445)	$ 185,255

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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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