Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation - Stock-based Compensation Expense Recognized (Detail)

v3.3.0.814
Stock-based Compensation - Stock-based Compensation Expense Recognized (Detail) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2015
Sep. 30, 2014
Sep. 30, 2015
Sep. 30, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]        
Total Stock based compensation $ 272,749 $ 34,109 $ 659,029 $ 290,830
Research and Development [Member]        
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]        
Total Stock based compensation 76,579 18,217 180,449 155,984
Selling, General and Administrative [Member]        
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]        
Total Stock based compensation $ 196,170 $ 15,892 $ 478,580 $ 134,846