Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation (Details)

v2.4.0.8
Stock-Based Compensation (Details) (USD $)
12 Months Ended 0 Months Ended 1 Months Ended 12 Months Ended
Jul. 31, 2014
Jul. 31, 2013
Jul. 31, 2012
Jul. 31, 2014
Minimum
Jul. 31, 2013
Minimum
Jul. 31, 2012
Minimum
Jul. 31, 2014
Maximum
Jul. 31, 2013
Maximum
Jul. 31, 2012
Maximum
Jul. 31, 2014
Research and development expense
Jul. 31, 2013
Research and development expense
Jul. 31, 2012
Research and development expense
Jul. 31, 2014
General and administrative expense
Jul. 31, 2013
General and administrative expense
Jul. 31, 2012
General and administrative expense
Jul. 31, 2014
Employees
Jul. 31, 2014
Employees
Minimum
Jul. 31, 2014
Employees
Maximum
Jul. 31, 2014
Consultant
Jul. 31, 2014
Consultant
Minimum
Jul. 31, 2014
Consultant
Maximum
Jul. 31, 2014
Non-employees
Research and development expense
Jul. 31, 2013
Non-employees
Research and development expense
Jul. 31, 2012
Non-employees
Research and development expense
Jul. 31, 2014
Non-employees
General and administrative expense
Jul. 31, 2013
Non-employees
General and administrative expense
Jul. 31, 2012
Non-employees
General and administrative expense
Jul. 18, 2014
2011 Plan
Apr. 15, 2013
2011 Plan
May 31, 2011
2011 Plan
May 31, 2011
2011 Plan
Minimum
May 31, 2011
2011 Plan
Maximum
Jul. 31, 2014
2011 Plan
Employees
Jul. 31, 2013
2011 Plan
Employees
Jul. 31, 2012
2011 Plan
Employees
Jul. 31, 2013
2011 Plan
Employees
Minimum
Jul. 31, 2013
2011 Plan
Employees
Maximum
Jul. 31, 2014
2011 Plan
Director
Jul. 31, 2013
2011 Plan
Director
Jul. 31, 2012
2011 Plan
Director
Jul. 31, 2014
2011 Plan
Consultant
Jul. 31, 2013
2011 Plan
Consultant
Jul. 31, 2012
2011 Plan
Consultant
Jul. 31, 2013
2011 Plan
Consultant
Minimum
Jul. 31, 2012
2011 Plan
Consultant
Minimum
Jul. 31, 2013
2011 Plan
Consultant
Maximum
Jul. 31, 2012
2011 Plan
Consultant
Maximum
Jul. 31, 2014
Outside 2011 Plan
Employees
Jul. 31, 2014
Outside 2011 Plan
Consultant
Stock-based compensation                                                                                                  
Number of additional shares authorized                                                       16,000,000 3,800,000                                        
Number of shares authorized                                                       25,000,000 9,000,000 5,200,000                                      
Purchase price of incentive stock options as a percentage of its fair value                                                             100.00%                                    
Term of stock options                               10 years       1 year 10 years                     10 years   10 years 10 years     10 years 10 years 10 years       3 years 3 years 10 years 10 years    
Provisional percentage of outstanding stock owned by stockholders                                                             10.00%                                    
Exercise price as a percentage of fair value of common stock for stockholders who own more than 10% of outstanding stock                                                             110.00%                                    
Options granted to purchase shares 9,020,000 3,015,000 3,260,000                                                           1,810,000 685,000 1,300,000     750,000 300,000 400,000 760,000 2,030,000 1,560,000         5,200,000 500,000
Vesting period                                 2 years 3 years                                 2 years 2 years 3 years 1 year 1 year 1 year                  
Exercise price, low end of the range (in dollars per share)                               $ 0.31     $ 0.26                             $ 0.20 $ 0.21         $ 0.21   $ 0.18 $ 0.18            
Exercise price, high end of the range (in dollars per share)                               $ 0.805     $ 0.805                             $ 0.42 $ 0.40         $ 0.40   $ 0.35 $ 0.39            
Exercise price (in dollars per share)                                                                           $ 0.805 $ 0.25                    
Expected volatility, minimum (as a percent) 83.62% 80.32% 85.96%                                                                                            
Expected volatility, maximum (as a percent) 93.27% 97.85% 125.00%                                                                                            
Risk-free interest rate, minimum (as a percent) 0.10% 0.31% 0.35%                                                                                            
Risk-free interest rate, maximum (as a percent) 2.78% 1.97% 2.08%                                                                                            
Expected forfeiture rate (as a percent) 0.00% 0.00% 0.00%                                                                                            
Expected term       1 year 3 years 3 years 10 years 10 years 10 years                                                                                
Stock-based compensation expense recognized $ 1,816,000 $ 452,000 $ 333,000             $ 666,000 $ 41,000 $ 89,000 $ 1,150,000 $ 411,000 $ 244,000             $ 118,000 $ 11,000 $ 25,000 $ 119,000 $ 289,000 $ 133,000                                            
Option Shares Outstanding                                                                                                  
Balance at the beginning of the period (in shares) 5,150,000 3,175,000                                                                                              
Granted (in shares) 9,020,000 3,015,000 3,260,000                                                           1,810,000 685,000 1,300,000     750,000 300,000 400,000 760,000 2,030,000 1,560,000         5,200,000 500,000
Exercised (in shares) (1,799,975) (766,500)                                                                                              
Forfeited/Cancelled (in shares) (609,125) (273,500) (85,000)                                                                                            
Balance at the end of the period (in shares) 11,760,900 5,150,000 3,175,000                                                                                            
Exercisable (in shares) 6,022,353                                                                                                
Weighted-Average Exercise Price                                                                                                  
Balance at the beginning of the period (in dollars per share) $ 0.23 $ 0.24                                                                                              
Granted (in dollars per share) $ 0.66 $ 0.22 $ 0.24                                                                                            
Exercised (in dollars per share) $ 0.21 $ 0.18                                                                                              
Forfeited/Cancelled (in dollars per share) $ 0.26 $ 0.33 $ 0.40                                                                                            
Balance at the end of the period (in dollars per share) $ 0.56 $ 0.23 $ 0.24                                                                                            
Exercisable (in dollars per share) $ 0.47                                                                                                
Aggregate Intrinsic Value                                                                                                  
Balance at the beginning of the period (in dollars) 372,000 24,000                                                                                              
Granted (in dollars) 1,000 232,000                                                                                              
Exercised (in dollars) 846,000 52,000                                                                                              
Forfeited/Cancelled (in dollars) 65,000 9,000                                                                                              
Balance at the end of the period (in dollars) 844,000 372,000 24,000                                                                                            
Exercisable (in dollars) $ 647,000