Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies (Details Textual)

v3.3.1.900
Summary of Significant Accounting Policies (Details Textual) - USD ($)
12 Months Ended
Apr. 10, 2015
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Summary Of Significant Accounting Policies [Line Items]        
Research and Development Expense, Total   $ 18,825,041 $ 12,511,647 $ 2,109,890
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount   4,994,425 3,261,360 3,525,904
Employee Stock Purchase Plan [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Common Stock, Capital Shares Reserved for Future Issuance 600,000 553,977    
Common Stock Purchase Price Discount Percentage 15.00%