Investments in Marketable Securities - Summary of Investments Classified As Available-For-Sale Securities (Detail) - USD ($)	Sep. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 16,623,402
Gross Unrealized Gains	975
Gross Unrealized Losses	(5,823)
Aggregate Estimated Fair Value	16,618,554	$ 0
Money market funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,269,047
Aggregate Estimated Fair Value	1,269,047
Certificates of deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	7,089,727
Aggregate Estimated Fair Value	7,089,727
Corporate debt securities, available-for-sale [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,264,628
Gross Unrealized Gains	975
Gross Unrealized Losses	(5,823)
Aggregate Estimated Fair Value	$ 8,259,780

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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This item represents the cost of debt and equity 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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