Fair Value Measurements - Additional Information (Detail)	3 Months Ended		9 Months Ended
	Jun. 30, 2015 USD ($) shares	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) shares	Jun. 30, 2014 USD ($)	Sep. 30, 2014 USD ($)	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 | $	$ 23,280,640		$ 23,280,640		$ 21,653,032
Investments | $	1,085,282		1,085,282		23,088,346
Total investments | $	24,365,922		24,365,922		44,741,378
Fair value of investment | $	$ 24,128,345		$ 24,128,345		$ 44,333,855
Warrants outstanding	1,437,011		1,437,011
Non-cash gain (loss) from change in fair value of the derivative liability | $	$ (102,763)	$ 737,072	$ 2,268,798	$ (5,680,540)
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		500,000
Non-cash gain (loss) from change in fair value of the derivative liability | $	$ (1,950)	$ 21,397	$ 177,605	$ (31,791)
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		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		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		12,123