Fair Value Measurements - Additional Information (Detail)	12 Months Ended
	Sep. 30, 2015 USD ($) shares	Sep. 30, 2014 USD ($)	Sep. 30, 2013 USD ($)	Sep. 30, 2011 shares	Jan. 31, 2013 shares	Dec. 31, 2012 shares	Jun. 30, 2010 shares
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short term investments | $	$ 17,539,902	$ 21,653,032
Fair value of investment | $	$ 17,234,960	44,333,855
Warrants outstanding	1,490,761
Non-cash gain (loss) from change in fair value of the derivative liability | $	$ 2,684,712	(5,821,796)	$ 5,066,591
Duration of exchange rights	7 years
Ablaris Therapeutics
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrants outstanding	500,000
Non-cash gain (loss) from change in fair value of the derivative liability | $	$ 184,555	$ (211,860)	$ 5,806
Exchange right convertible conversion ratio for first year	0.06
Exchange right convertible conversion ratio for second year	0.04
Exchange right convertible conversion ratio for third year	0.03
Exchange right convertible conversion ratio for fourth year	0.02
Exchange right convertible conversion ratio for fifth year and beyond	0.01
Number of exchange right sold				675,000
2010 Warrants
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrants issued to acquire Common Stock							329,649
Warrants outstanding	24,324
2012 Warrants
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrants issued to acquire Common Stock						912,543
Warrants outstanding	265,161
2013 Warrants
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrants issued to acquire Common Stock					833,530
Warrants outstanding	12,123