Annual report pursuant to Section 13 and 15(d)

Related Party Transactions - Additional Information (Detail)

v3.5.0.2
Related Party Transactions - Additional Information (Detail) - USD ($)
12 Months Ended
May 10, 2016
Jun. 23, 2015
May 31, 2016
Jan. 19, 2016
May 31, 2015
Related Party Transaction [Line Items]          
Warrants to purchase common shares, shares     795,593    
Private Equity Offering          
Related Party Transaction [Line Items]          
Proceeds from private equity offering     $ 37,600,000    
Shares of common stock sold at private equity offering     48,659,338    
Exercise price of warrants, per share     $ 0.675    
Alpha Venture Capital Partners, L.P. | 3-Month Unsecured Convertible Promissory Note          
Related Party Transaction [Line Items]          
Convertible note, face amount         $ 1,500,000
Alpha Venture Capital Partners, L.P. | Private Equity Offering          
Related Party Transaction [Line Items]          
Warrants to purchase common shares, shares     1,000,000    
Alpha Venture Capital Partners, L.P. | 2-Year Unsecured Convertible Promissory Note          
Related Party Transaction [Line Items]          
Convertible note, face amount         $ 2,000,000
Alpha Venture Capital Partners, L.P. | AVCP Convertible Notes          
Related Party Transaction [Line Items]          
Common stock issued upon conversion of notes   5,237,966      
Alpha Venture Capital Partners, L.P. | AVCP Convertible Notes | Additional 5-year Warrant          
Related Party Transaction [Line Items]          
Common stock issued upon conversion of notes   1,000,000      
Exercise price of warrants, per share   $ 0.675      
Denis R. Burger, Ph.D | Consulting Agreement          
Related Party Transaction [Line Items]          
Compensation payable per month       $ 20,000  
Jordan G. Naydenov | Private Equity Offering          
Related Party Transaction [Line Items]          
Proceeds from private equity offering $ 1,000,000        
Shares of common stock sold at private equity offering 1,000,000        
Warrants to purchase common shares, shares 250,000        
Exercise price of warrants, per share $ 1.35