Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Additional Information (Detail)

v3.8.0.1
Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)
 3 Months Ended 12 Months Ended
Aug. 31, 2017
Aug. 31, 2016
May 31, 2017
Aug. 24, 2017
Aug. 24, 2016
Mar. 18, 2016
Mar. 17, 2016
Apr. 30, 2010
Summary Of Significant Accounting Policies [Line Items]                
Net loss $ (11,628,273) $ (5,354,385)            
Accumulated (deficit) (134,617,989)   $ (122,989,715)          
Balance in excess of federally insured limits 700,000   1,500,000          
Impairment charges 0 $ 0            
Pre-launch inventory qualified for capitalization $ 0   $ 0          
Estimated future unvested forfeitures 0.00%              
Common stock, shares authorized 350,000,000   350,000,000 375,000,000 350,000,000 250,000,000 200,000,000 100,000,000
Amortization of discount on convertible notes $ 444,152              
Direct costs associated with the convertible notes 436,000              
Amortization of debt issuance costs $ 113,700              
Common stock options and warrants to purchase 80,582,715 62,588,165            
Unrecognized benefits $ 0              
Equity Securities                
Summary Of Significant Accounting Policies [Line Items]                
Deferred offering costs     $ 1,800,000          
Short-Term Convertible Notes                
Summary Of Significant Accounting Policies [Line Items]                
Debt discount 1,222,000   92,000          
Amortization of debt issuance costs 114,000              
Short-Term Convertible Notes | Detachable Common Stock Warrants                
Summary Of Significant Accounting Policies [Line Items]                
Debt discount 1,600,000   92,000.0          
Amortization of discount on convertible notes $ 444,000   $ 0          
Series B Convertible Preferred Stock                
Summary Of Significant Accounting Policies [Line Items]                
Preferred Stock Shares authorized to be issued 400,000   400,000          
Common stock options and warrants to purchase 92,100   92,100          
Common shares issued upon conversion of preferred stock 921,000              
Maximum                
Summary Of Significant Accounting Policies [Line Items]                
Preferred Stock Shares authorized to be issued 5,000,000