CONSOLIDATED STATEMENTS OF STOCKHOLDERS' (EQUITY) DEFICIT (USD $) In Thousands, except Share data, unless otherwise specified	Total	Parent	Preferred Stock	Common Stock	Additional Paid-in-Capital	Accumulated Deficit
Balance at Sep. 30, 2011		$ (28,459)	$ 1	$ 245	$ 1,824,433	$ (1,853,138)
Balance (in shares) at Sep. 30, 2011			135,000	24,471,000
Increase (Decrease) in Stockholders' Equity
Net loss	(1,112)	(1,112)				(1,112)
Compensation expense related to stock options, awards and ESPP		4,442			4,442
Issuance of common stock upon exercise of stock options (in shares)				6,000
Issuance of common stock upon exercise of stock options		16			16
Issuance of shares under ESPP (in shares)				821,000
Issuance of shares under employee stock purchase plan		1,737		8	1,729
Release of restricted stock units (in shares)				721,000
Release of restricted stock units				7	(7)
Repurchase and retirement of restricted stock units for payroll taxes (in shares)				(207,000)
Repurchase and retirement of restricted stock units for payroll taxes		(639)		(2)	(637)
Balance at Sep. 30, 2012		(24,015)	1	258	1,829,976	(1,854,250)
Balance (in shares) at Sep. 30, 2012			135,000	25,812,000
Increase (Decrease) in Stockholders' Equity
Net loss	(22,078)	(22,078)				(22,078)
Compensation expense related to stock options, awards and ESPP		4,396			4,396
Issuance of common stock upon exercise of stock options (in shares)				9,000
Issuance of common stock upon exercise of stock options		20			20
Issuance of shares under ESPP (in shares)				953,000
Issuance of shares under employee stock purchase plan		1,666		9	1,657
Issuance of common stock, net of offering costs (in shares)				29,371,000
Issuance of common stock, net of offering costs		54,441		294	54,147
Conversion of Series B Preferred Shares (in shares)			(135,000)	674,000
Conversion of Series B Preferred Shares			(1)	7	(6)
Release of restricted stock units (in shares)				1,045,000
Release of restricted stock units				10	(10)
Repurchase and retirement of restricted stock units for payroll taxes (in shares)				(319,000)
Repurchase and retirement of restricted stock units for payroll taxes		(618)		(3)	(615)
Reclassification of compound embedded derivative liability to additional paid-in capital		2,096			2,096
Balance at Sep. 30, 2013		15,908		575	1,891,661	(1,876,328)
Balance (in shares) at Sep. 30, 2013				57,545,000
Increase (Decrease) in Stockholders' Equity
Net loss	(18,075)	(18,075)				(18,075)
Compensation expense related to stock options, awards and ESPP		6,075			6,075
Issuance of common stock upon exercise of stock options (in shares)				52,000
Issuance of common stock upon exercise of stock options		122		1	121
Issuance of shares under ESPP (in shares)				722,000
Issuance of shares under employee stock purchase plan		1,815		7	1,808
Issuance of common stock, net of offering costs (in shares)				8,582,000
Issuance of common stock, net of offering costs		26,605		86	26,519
Release of restricted stock units (in shares)				1,183,000
Release of restricted stock units				12	(12)
Repurchase and retirement of restricted stock units for payroll taxes (in shares)				(381,000)
Repurchase and retirement of restricted stock units for payroll taxes		(1,254)		(4)	(1,250)
Other		62			62
Balance at Sep. 30, 2014		$ 31,258		$ 677	$ 1,924,984	$ (1,894,403)
Balance (in shares) at Sep. 30, 2014				67,703,000