Equity (Schedule of Common Stock Reserved for Future Issuances) (Details)	Jun. 30, 2013	Sep. 30, 2012
Equity [Abstract]
Exercise of outstanding stock options	1,774,972	2,032,215
Unvested restricted stock units	957,867
Purchases under the employee stock purchase plan	636,001
Issuance of stock-based awards under the Equity Plans	584,730
Exercise of outstanding warrants	400,001	750,011
Purchases under the officer and director share purchase plan	93,745
Total reserved	4,447,316