Quarterly report pursuant to Section 13 or 15(d)

Stock Options and Warrants - Additional Information (Detail)

v3.8.0.1
Stock Options and Warrants - Additional Information (Detail) - USD ($)
1 Months Ended 3 Months Ended 6 Months Ended 12 Months Ended
Dec. 29, 2017
Dec. 21, 2017
Nov. 30, 2017
Nov. 24, 2017
Oct. 11, 2017
Sep. 08, 2017
Jun. 14, 2017
Feb. 28, 2017
Jan. 31, 2017
Dec. 12, 2016
Dec. 20, 2017
Sep. 30, 2016
Nov. 30, 2017
Nov. 30, 2016
Nov. 30, 2017
Nov. 30, 2016
May 31, 2017
Aug. 24, 2017
Jun. 19, 2017
Mar. 31, 2016
Feb. 28, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Stock options grant date fair value                             $ 0.25            
Common Stock issued     165,135,154                   165,135,154   165,135,154   149,468,244        
Proceeds from Issuance of Common Stock                             $ 8,990,000            
Inducement interest related to warrant extensions                             826,252            
Compensation expense                             $ 529,617 $ 687,634          
Convertible Notes 2017                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Warrants to purchase common shares, shares                                     383,333    
Minimum | Convertible Notes 2017                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Exercise price of warrants, per share             $ 1.00                            
Warrant covering common stock shares purchased, percentage             25.00%                            
Maximum | Convertible Notes 2017                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Exercise price of warrants, per share             $ 1.35                            
Warrant covering common stock shares purchased, percentage             50.00%                            
Placement Agent                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Warrants to purchase common shares, shares     350,766   150,461 213,573   453,652 122,799     1,066,667 350,766   350,766            
Term of warrants         5 years 5 years   5 years 5 years     5 years     5 years            
Exercise price of warrants, per share     $ 0.825   $ 0.715 $ 0.825   $ 0.825 $ 0.825     $ 0.825 $ 0.825   $ 0.825            
Investor                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Exercise price of warrants, per share     $ 0.50                   $ 0.50   $ 0.50            
Common Stock issued     3,295,000                   3,295,000   3,295,000            
Proceeds from Issuance of Common Stock                             $ 1,600,000            
Securities Purchase Agreement                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Warrants to purchase common shares, shares     3,258,990             2,000,000   6,666,667 3,258,990   3,258,990            
Term of warrants                   5 years   5 years     5 years            
Exercise price of warrants, per share     $ 1.00             $ 1.00   $ 1.00 $ 1.00   $ 1.00            
Proceeds from Issuance of Common Stock                   $ 3,000,000   $ 9,000,000                  
Subscription Agreements                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Warrants to purchase common shares, shares         940,380 1,668,163   2,835,323 767,498                        
Term of warrants         5 years 5 years   5 years 5 years                        
Exercise price of warrants, per share         $ 0.75 $ 1.00   $ 1.00 $ 1.00                        
Proceeds from Issuance of Common Stock         $ 1,100,000 $ 2,300,000   $ 3,800,000 $ 1,000,000                        
Make-Whole Securities                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Warrants to purchase common shares, shares     251,504                   251,504   251,504            
Term of warrants     5 years                                    
Exercise price of warrants, per share     $ 0.75                   $ 0.75   $ 0.75            
Make-Whole Securities | Placement Agent                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Warrants to purchase common shares, shares     26,702                   26,702   26,702            
Term of warrants     5 years                                    
Exercise price of warrants, per share     $ 0.715                   $ 0.715   $ 0.715            
Before Inducement | Investor                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Exercise price of warrants, per share     $ 1.00                   $ 1.00   $ 1.00            
Class of warrant or right expiration date                             Jun. 30, 2017            
Private Equity Offering                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Warrants to purchase common shares, shares     6,651,800                   6,651,800   6,651,800            
Term of warrants                             5 years   5 years        
Exercise price of warrants, per share     $ 0.75                   $ 0.75   $ 0.75   $ 1.00        
Warrant covering common stock shares purchased, percentage                             100.00%   25.00%        
Private Equity Offering | Subsequent Event                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Warrants to purchase common shares, shares 1,777,638                   2,948,666                    
Term of warrants 5 years                   5 years                    
Exercise price of warrants, per share $ 0.75                   $ 0.75                    
Warrant covering common stock shares purchased, percentage 100.00%                   100.00%                    
Private Equity Offering | Placement Agent                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Warrants to purchase common shares, shares     452,180                   452,180   452,180            
Term of warrants                             5 years            
Exercise price of warrants, per share     $ 0.55                   $ 0.55   $ 0.55            
Private Equity Offering | Placement Agent | Subsequent Event                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Warrants to purchase common shares, shares 177,764                   243,667                    
Exercise price of warrants, per share $ 0.55                   $ 0.55                    
2012 Equity Incentive Plan                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Compensation expense                         $ 275,000 $ 335,000 $ 530,000 688,000          
Grant date fair value of options and warrants                         127,000 $ 279,000 574,000 $ 530,000          
Unrecognized compensation expense     $ 1,000,000                   $ 1,000,000   $ 1,000,000            
Weighted average period over which unrecognized compensation expense is expected to be recognized                             1 year 5 months 5 days            
2012 Equity Incentive Plan | Stock Options                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Shares available for future stock-based grants     5,693,807                   5,693,807   5,693,807            
2012 Equity Incentive Plan | Stock Options | Before Amendment                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Shares available for future issuance                                   7,000,000   5,000,000 3,000,000
2012 Equity Incentive Plan | Stock Options | After Amendment                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Shares available for future issuance                                   15,000,000   7,000,000 5,000,000
2012 Equity Incentive Plan | Stock Options | Directors                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Stock options granted, shares                             450,000            
Stock options granted, exercise price                             $ 0.57            
Stock options grant date fair value                             $ 0.36            
2012 Equity Incentive Plan | Stock Options | Directors | Minimum                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Vesting period                             1 year            
2012 Equity Incentive Plan | Stock Options | Directors | Maximum                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Vesting period                             10 years            
2012 Equity Incentive Plan | Stock Options | Chief Science Officer                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Stock options granted, shares                             600,000            
Stock options granted, exercise price                             $ 0.57            
Vesting period                             3 years            
Stock options grant date fair value                             $ 0.35            
Stock options, term                             10 years            
2012 Equity Incentive Plan | Stock Options | Executive Management and Employees                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Stock options granted, shares                             800,000            
Vesting period                             3 years            
Stock options grant date fair value                             $ 0.35            
Stock options, term                             10 years            
Stock options granted, exercise price, lower range limit                             $ 0.57            
2012 Equity Incentive Plan | Warrants (equity allocation) | Consultant 1                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Vesting period                             5 years            
Warrants granted, shares                             200,000            
Warrants granted, exercise price                             $ 0.64            
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage                             25.00%            
Warrants grant date fair value                             $ 0.26            
2012 Equity Incentive Plan | Warrants (equity allocation) | Consultant 2                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Vesting period                             5 years            
Warrants granted, shares                             100,000            
Warrants granted, exercise price                             $ 0.75            
Warrants grant date fair value                             $ 0.29            
2012 Equity Incentive Plan | Warrants (equity allocation) | December 31, 2017 | Consultant 1                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage                             25.00%            
2012 Equity Incentive Plan | Warrants (equity allocation) | Milestone | Consultant 1                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage                             50.00%            
Offer to Amend and Exercise                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Warrants to purchase common shares, shares       51,090,113                                  
Exercise price of warrants, per share       $ 0.50                                  
Offer to Amend and Exercise | Subsequent Event                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Class of warrant or right expiration date   Jan. 26, 2018                                      
Offer to Amend and Exercise | Minimum                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Exercise price of warrants, per share       $ 0.50                                  
Expiration of tender offer       2018-10                                  
Offer to Amend and Exercise | Maximum                                          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                          
Exercise price of warrants, per share       $ 1.35                                  
Expiration of tender offer       2022-10