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Fair Value Measurements - Reconciliation of Derivative Liability (Detail) - USD ($) | 12 Months Ended
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Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2013
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |  |
Change in value | $ 2,684,712 | $ (5,821,796) | $ 5,066,591
Exchange rights |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |  |
Value, Beginning balance | 216,429 | 4,569 |
Change in value | (184,555) | 211,860 |
Net settlements | (3,072) |  |
Value, Ending balance | 28,802 | 216,429 | 4,569
Warrant |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |  |
Value, Beginning balance | 3,957,514 | 4,091,797 |
Change in value | (2,684,712) | 5,821,796 |
Net settlements |  | (5,956,079) |
Value, Ending balance | $ 1,272,802 | $ 3,957,514 | $ 4,091,797

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- Definition Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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