Quarterly report pursuant to Section 13 or 15(d)

Subsequent events - Additional Information (Detail)

v3.3.1.900
Subsequent events - Additional Information (Detail)
 1 Months Ended 6 Months Ended
Jan. 04, 2016
$ / shares
shares
Dec. 21, 2015
$ / shares
shares
Dec. 15, 2015
USD ($)
Dec. 15, 2015
GBP (£)
Dec. 14, 2015
USD ($)
Dec. 04, 2015
$ / shares
shares
Dec. 31, 2015
USD ($)
$ / shares
shares
Nov. 30, 2015
USD ($)
$ / shares
Subsequent Event [Line Items]                
Cash payment, as a fee to the placement agent | $               $ 1,433,569
Private Equity Offering                
Subsequent Event [Line Items]                
Warrant exercise price | $ / shares               $ 0.75
Subsequent Event                
Subsequent Event [Line Items]                
License payment     $ 915,000 £ 600,000 $ 915,000      
Subsequent Event | Private Equity Offering                
Subsequent Event [Line Items]                
Number of shares issued             7,876,265  
Number of common stock warrants issued             3,938,121  
Warrant exercise price | $ / shares             $ 0.75  
Proceeds from private equity offering | $             $ 5,900,000  
Number of warrants to be issued, as a fee to the placement agent             919,913  
Cash payment, as a fee to the placement agent | $             $ 700,000  
Warrant exercise term             5 years  
Subsequent Event | Stock Options | Directors                
Subsequent Event [Line Items]                
Share based compensation arrangement by share based payment award, options, grants in period, gross           100,000    
Stock options granted, exercise price | $ / shares           $ 0.84    
Share-based compensation arrangement by share-based payment award, expiration date           Dec. 04, 2025    
Remaining authorization to issue equity awards under the 2012 Equity Incentive Plan           304,930    
Subsequent Event | Stock Options | Directors | Stock Option Grant Date                
Subsequent Event [Line Items]                
Percentage of option awards vesting           50.00%    
Subsequent Event | Stock Options | Directors | First Anniversary Of Grant Date                
Subsequent Event [Line Items]                
Percentage of option awards vesting           50.00%    
Subsequent Event | Equity Incentive Plan 2012                
Subsequent Event [Line Items]                
Share based compensation arrangement by share based payment award, options, grants in period, gross 304,000              
Remaining authorization to issue equity awards under the 2012 Equity Incentive Plan 930              
Share price | $ / shares $ 0.75              
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition 10 years              
Subsequent Event | Incentive Plans                
Subsequent Event [Line Items]                
Share-based compensation arrangement by share-based payment award, expiration period   5 years            
Share-based compensation arrangement by share-based payment award, extended expiration period   5 years            
Share price | $ / shares   $ 0.81            
Share-based compensation arrangement by share-based payment award, options outstanding   1,924,513            
Share-based compensation arrangement by share-based payment award, options, weighted average exercise price | $ / shares   $ 1.39            
Subsequent Event | Incentive Plans | Minimum                
Subsequent Event [Line Items]                
Share-based compensation arrangement by share-based payment award, expiration date   Jul. 31, 2021            
Subsequent Event | Incentive Plans | Maximum                
Subsequent Event [Line Items]                
Share-based compensation arrangement by share-based payment award, expiration date   Jun. 30, 2025