Financial Instruments - Cash and Cash Equivalents Held in Investment Portfolio (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 32,212,589	$ 30,585,424
Gross Unrealized (Losses)
Fair Value	32,212,589	30,585,424
Cash [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	226,349	1,355,281
Gross Unrealized (Losses)
Fair Value	226,349	1,355,281
Cash equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	31,986,240	29,230,143
Gross Unrealized (Losses)
Fair Value	$ 31,986,240	$ 29,230,143

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

No definition available.

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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