Stockholders' Equity - Additional Information (Detail) (USD $)	0 Months Ended			1 Months Ended				12 Months Ended				1 Months Ended	0 Months Ended	1 Months Ended	12 Months Ended		0 Months Ended		0 Months Ended		1 Months Ended			1 Months Ended
	Feb. 24, 2014	Oct. 11, 2013	Aug. 10, 2012	May 31, 2013	Jan. 31, 2013	Dec. 31, 2012	Nov. 17, 2011	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012	Oct. 21, 2011	Nov. 17, 2011 Roche	Oct. 21, 2011 Common Stock	May 31, 2013 Common Stock	Sep. 30, 2014 Common Stock	Sep. 30, 2012 Common Stock	Oct. 21, 2011 Subscription Agreement	Sep. 30, 2014 Series B Preferred Stock	Oct. 11, 2013 Series C Preferred Stock	Sep. 30, 2014 Series C Preferred Stock	Feb. 29, 2012 Series A Preferred Stock	Oct. 31, 2011 Series A Preferred Stock	Oct. 21, 2011 Series A Preferred Stock	Oct. 31, 2011 Series A Preferred Stock Subscription Agreement	May 31, 2013 Series B convertible preferred stock	Sep. 30, 2014 2000 Stock Option Plan, 2004 Equity Incentive Plan, 2013 Equity Incentive Plan, and Inducement Grants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Capital stock authorized for issuance								150,000,000
Common stock, shares authorized								145,000,000	145,000,000
Common stock, par value								$ 0.001	$ 0.001		$ 0.001
Preferred stock, shares authorized								5,000,000	5,000,000
Preferred stock, par value								$ 0.001	$ 0.001														$ 0.001
Common stock, shares outstanding								54,656,936	32,489,444									1,256,831		2,730,375
Preferred stock, shares outstanding								18,300	9,900									2,300		16,000
Share reserve for issuance																										7,165,174
Threshold percentage of common stock ownership upon preferred stock conversion								9.99%
Issuance and sale of Common Stock	6,325,000	3,071,672	2,260,869		1,667,051	1,825,079								14,300,000			675,000		46,000					1,015	9,900
Sale of stock, price per share	$ 18.95	$ 5.86	$ 2.76		$ 2.12	$ 2.26							$ 3.70	$ 1.83					$ 1,000				$ 1,000		$ 1,000
Issuance of preferred stock in subsidiary																						$ 1,015,000
Number of shares converted in common stock																					1,015	1,015
Preferred stock converted to common stock, Shares															9,272,459	275,782					275,782
Aggregate purchase price on issuance of common stock to be received													2,497,500
Unit sold, description			Each unit consisted of one share of Common Stock and a warrant to purchase		Each unit consisted of one share of Common Stock and a warrant to purchase	Each unit consisted of one share of Common Stock and a warrant to purchase
Warrant to purchase common stock			0.75		0.5
Common stock exercise price			$ 3.25
Proceeds from issuance of common stock and warrants, net	112,600,000	60,000,000	6,200,000		3,500,000	4,100,000
Exercise price of warrant								$ 1.83
Ratio of Common Stock to purchase for 1 Warrant						0.5
Conversion price		$ 5.86		$ 1.83
Cash from issuance of equity				36,000,000				172,641,671	42,448,826	10,883,992
Warrants issued				0
Aggregate price on issuance or Sale of equity		$ 64,000,000
Reverse stock split ratio												0.1
Fractional shares of common stock issued in connection of reverse stock split							0									131