Quarterly report pursuant to Section 13 or 15(d)

Common Stock - Additional Information (Detail)

v3.8.0.1
Common Stock - Additional Information (Detail) - USD ($)
 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Dec. 31, 2016
Schedule Of Stockholders Equity [Line Items]      
Common stock, shares authorized 300,000,000   300,000,000
Common stock, par value $ 0.001   $ 0.001
Common stock, shares issued 44,704,849   43,058,827
Common stock, outstanding 44,704,849   43,058,827
Cash received from option exercises $ 366,200    
Cash proceeds from exercise of warrants $ 3,126,778    
Common Stock [Member]      
Schedule Of Stockholders Equity [Line Items]      
Number of shares, Options exercised 232,017 0  
Cash received from option exercises $ 400,000    
Number of common stock issued upon exercise of warrants 1,414,005    
Cash proceeds from exercise of warrants $ 3,100,000    
Number of warrants exercised   0  
Cash Less Exercise Provision [Member] | Common Stock [Member]      
Schedule Of Stockholders Equity [Line Items]      
Number of shares, Options exercised 66,392    
Stock options to purchase shares of common stock 150,000    
Number of shares, warrants to purchase common stock 89,330    
Number of common stock issued upon exercise of warrants as cashless 49,127    
Cash Based Awards [Member] | Common Stock [Member]      
Schedule Of Stockholders Equity [Line Items]      
Number of shares, Options exercised 165,625    
Number of common stock issued upon exercise of warrants 1,364,878