Contractual Maturities of Debt Securities (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Due in 1 year or less	$ 21,792,154
Due in 1 to 2 years	12,225,297
Available-for-sale Debt Securities, Amortized Cost Basis, Total	34,017,451
Due in 1 year or less	21,793,550
Due in 1 to 2 years	12,218,602
Fair Value	$ 34,012,152	$ 20,760,050

Available for Sale Securities, Debt Maturities, after One Through Two Years, Fair Value

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Available for sale Securities, Debt Maturities, One Through Two Years, Amortized Cost

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This item represents the cost of debt 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.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at fair value maturing in the next fiscal year following the latest fiscal year.

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