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Fair Value Measurements - Reconciliation of Derivative Liability (Detail) - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 31, 2017 | Mar. 31, 2016 | Mar. 31, 2017 | Mar. 31, 2016
Exchange rights |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |  |  |
Value, Beginning balance |  |  | $ 36,752 |
Change in value |  |  | (27,500) |
Value, Ending balance | $ 9,252 |  | 9,252 |
Warrant |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |  |  |
Value, Beginning balance |  |  | 1,565,874 |
Change in value | 25,883 | $ (363,285) | (1,428,948) | $ (341,711)
Value, Ending balance | $ 136,926 |  | $ 136,926 |

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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=66048111&loc=d3e19207-110258 + Details
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