Contractual Maturities of Money Market Funds and Marketable Securities (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Due in 1 year or less	$ 21,546,789
Due in 1 to 2 years	10,912,224
Amortized Cost	32,459,013	34,017,451
Due in 1 year or less	21,551,398
Due in 1 to 2 years	10,904,518
Fair Value	$ 32,455,916	$ 34,012,152

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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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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