Fair Value Measurements - Reconciliation of Derivative Liability (Detail) - USD ($)	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Change in value	$ (293,072)	$ 2,684,712	$ (5,821,796)
Exchange rights
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Value, Beginning balance	28,802
Change in value	7,950
Value, Ending balance	36,752	28,802
Warrant
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Value, Beginning balance	1,272,802
Change in value	293,072
Value, Ending balance	$ 1,565,874	$ 1,272,802