Summary of Significant Accounting Policies (Details) (USD $)	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Share-Based compensation expense related to all of the Company's share-based awards
Share-based compensation expense, total	$ 1,789,302	$ 1,234,250	$ 3,196,310	$ 2,396,287
Research and development expense [Member]
Share-Based compensation expense related to all of the Company's share-based awards
Share-based compensation expense, total	287,669	267,133	555,813	507,935
Selling and marketing expense [Member]
Share-Based compensation expense related to all of the Company's share-based awards
Share-based compensation expense, total	419,066	235,196	734,595	365,072
General and administrative expense [Member]
Share-Based compensation expense related to all of the Company's share-based awards
Share-based compensation expense, total	1,082,567	731,921	1,905,902	1,523,280
Stock options [Member]
Share-Based compensation expense related to all of the Company's share-based awards
Share-based compensation expense, total	1,071,664	930,430	2,119,650	1,740,965
Restricted stock units [Member]
Share-Based compensation expense related to all of the Company's share-based awards
Share-based compensation expense, total	$ 717,638	$ 303,820	$ 1,076,660	$ 655,322