Quarterly report pursuant to sections 13 or 15(d)

Stock-Based Compensation (Details)

v2.4.0.6
Stock-Based Compensation (Details) (USD $)
3 Months Ended 9 Months Ended 3 Months Ended 9 Months Ended 3 Months Ended 9 Months Ended 3 Months Ended 9 Months Ended 3 Months Ended 9 Months Ended 1 Months Ended 3 Months Ended 0 Months Ended
Apr. 30, 2013
Apr. 30, 2012
Apr. 30, 2013
Apr. 30, 2012
Apr. 30, 2013
Maximum
Apr. 30, 2012
Maximum
Apr. 30, 2013
Maximum
Apr. 30, 2012
Maximum
Apr. 30, 2013
Minimum
Apr. 30, 2012
Minimum
Apr. 30, 2013
Minimum
Apr. 30, 2012
Minimum
Apr. 30, 2013
Research and development expense
Apr. 30, 2013
Research and development expense
Apr. 30, 2013
General and administrative expense
Apr. 30, 2013
General and administrative expense
May 31, 2011
2011 Plan
May 31, 2011
2011 Plan
Maximum
May 31, 2011
2011 Plan
Minimum
Apr. 30, 2013
2011 Plan
Employees
Oct. 31, 2012
2011 Plan
Employees
Oct. 31, 2012
2011 Plan
Employees
Maximum
Oct. 31, 2012
2011 Plan
Employees
Minimum
Jan. 31, 2013
2011 Plan
Consultant
Oct. 31, 2012
2011 Plan
Consultant
Apr. 30, 2013
2011 Plan
Director
Apr. 30, 2013
2011 Plan
Employees and directors
Apr. 15, 2013
Amended 2011 Plan
Stock-based compensation                                                        
Number of additional shares authorized                                 5,200,000                     3,800,000
Number of shares authorized                                                       9,000,000
Purchase price of incentive stock options as a percentage of its fair value                                     100.00%                  
Term of stock options                                   10 years   10 years 10 years     10 years 3 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     2,200,000                                   155,000     30,000 1,200,000   815,000  
Vesting period                                       3 years   3 years 2 years 1 year   1 year    
Exercise price, high end of the range (in dollars per share)                                       $ 0.26 $ 0.42              
Exercise price, low end of the range (in dollars per share)                                       $ 0.23 $ 0.20              
Exercise price (in dollars per share)                                               $ 0.35 $ 0.18 $ 0.25    
Expected volatility, minimum (as a percent) 81.92% 85.96% 81.92% 85.96%                                                
Expected volatility, maximum (as a percent) 97.85% 125.00% 97.85% 125.00%                                                
Risk-free interest rate (as a percent)         1.97% 2.08% 1.97% 2.08% 0.31% 0.82% 0.31% 0.82%                                
Expected forfeiture rate (as a percent) 0.00% 0.00% 0.00% 0.00%                                                
Expected term         10 years 10 years 10 years 10 years 3 years 5 years 3 years 5 years                                
Forfeiture rate (as a percent) 0.00%   0.00%                                                  
Stock-based compensation expense recognized $ 90,000   $ 357,000                   $ 1,000 $ 32,000 $ 89,000 $ 325,000                        
Option Shares Outstanding                                                        
Balance at the beginning of the period (in shares)     3,175,000                                                  
Granted (in shares)     2,200,000                                   155,000     30,000 1,200,000   815,000  
Exercised (in shares)     (750,000)                                                  
Forfeited/Cancelled (in shares)     (273,500)                                                  
Balance at the end of the period (in shares) 4,351,500   4,351,500                                                  
Weighted-Average Exercise Price                                                        
Balance at the beginning of the period (in dollars per share)     $ 0.24                                                  
Granted (in dollars per share)     $ 0.21                                                  
Exercised (in dollars per share)     $ 0.18                                                  
Forfeited/Cancelled (in dollars per share)     $ 0.33                                                  
Balance at the end of the period (in dollars per share) $ 0.23   $ 0.23                                                  
Aggregate Intrinsic Value                                                        
Balance at the beginning of the period (in dollars)     24,000                                                  
Granted (in dollars)     165,000                                                  
Exercised (in dollars)     50,000                                                  
Balance at the end of the period (in dollars) $ 275,000   $ 275,000