COMPUTATION OF NET LOSS PER SHARE Schedule of Potential Common Shares Excluded from the Diluted Computation (Details) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potential common shares excluded from calculation	14,944	16,697	16,898
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potential common shares excluded from calculation	2,940	2,089	1,813
Outstanding restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potential common shares excluded from calculation	2,328	2,021	1,686
Employee Stock Purchase Plan shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potential common shares excluded from calculation	491	368	506
Convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potential common shares excluded from calculation	0	0	674
2014 Debentures
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potential common shares excluded from calculation	7,298	10,332	10,332
Term B Loan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potential common shares excluded from calculation	1,887	1,887	1,887