Fair Value Measurements - Reconciliation of Derivative Liability (Detail) (USD $)	3 Months Ended	12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Change in value	$ 3,519,579
Warrant
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Value, Beginning balance	4,091,797	626,195
Issuance of instruments		2,153,819
Change in value	3,507,496	5,066,591
Net settlements	(2,518,502)	(3,754,808)
Value, Ending balance	5,080,791	4,091,797
Exchange rights
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Value, Beginning balance	4,569	10,375
Issuance of instruments
Change in value	12,082	(5,806)
Net settlements
Value, Ending balance	$ 16,651	$ 4,569