Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity (Details)

v3.7.0.1
Stockholders' Equity (Details)
1 Months Ended 12 Months Ended
Jan. 05, 2017
USD ($)
$ / shares
shares
Jan. 06, 2016
USD ($)
$ / shares
shares
Mar. 14, 2014
USD ($)
$ / shares
shares
Jun. 16, 2016
USD ($)
$ / shares
shares
Jan. 21, 2015
USD ($)
$ / shares
shares
Jul. 31, 2017
USD ($)
$ / shares
shares
Jul. 31, 2016
USD ($)
$ / shares
shares
Jul. 31, 2015
USD ($)
$ / shares
shares
Dec. 31, 2014
shares
Jan. 14, 2011
shares
Stockholders' Equity (Details) [Line Items]                    
Common Stock, Par or Stated Value Per Share (in Dollars per share) | $ / shares           $ 0.01 $ 0.01      
Percentage of Commission Payable on Equity Offering           3.00%        
Maximum Offering Price Under Sales Agreement           20,000,000     20,000,000  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value (in Dollars) | $           $ 10,530,000 $ 4,399,000 $ 97,000    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value (in Dollars) | $           14,510,000 6,451,000 $ 154,000    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value (in Dollars) | $           $ 1,388,000 $ 64,000      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross           496,996 490,473 383,873    
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share) | $ / shares           $ 7.07 $ 4.48 $ 3.55    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share) | $ / shares           $ 2.43 $ 1.58 $ 1.36    
Senior Officers and Board of Directors [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period 2 years       2 years          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross 264,896       293,373          
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share) | $ / shares $ 7.07       $ 3.40          
Share Based Compensation Arrangement by Share Based Payment Award Options Term 5 years       5 years          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share) | $ / shares $ 2.40       $ 1,270,000          
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term 3 years 3 months       3 years 3 months          
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate 46.28%       52.25%          
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate 1.48%       0.93%          
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Payments (in Dollars) | $ $ 0       $ 0          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares 0                  
Number of Officers         2          
Senior Management and Employees [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period 3 years   3 years              
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross 229,100   191,600              
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share) | $ / shares $ 7.07   $ 4.35              
Share Based Compensation Arrangement by Share Based Payment Award Options Term 5 years   5 years              
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share) | $ / shares $ 2.48   $ 1.57              
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term 3 years 6 months   3 years 6 months              
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate 45.85%   48.14%              
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate 1.54%   1.24%              
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Payments (in Dollars) | $ $ 0   $ 0              
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares 0   61,366              
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares     6,167              
Senior Officers [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period     2 years              
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross     110,000              
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share) | $ / shares     $ 4.35              
Share Based Compensation Arrangement by Share Based Payment Award Options Term     5 years              
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share) | $ / shares     $ 1.46              
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term     3 years 3 months              
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate     46.13%              
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate     1.19%              
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Payments (in Dollars) | $     $ 0              
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares     55,000              
Employees [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period       2 years            
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross       2,000            
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share) | $ / shares       $ 5.61            
Share Based Compensation Arrangement by Share Based Payment Award Options Term       5 years            
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share) | $ / shares       $ 1.88            
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term       3 years 3 months            
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate       46.64%            
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate       0.846%            
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Payments (in Dollars) | $       $ 0            
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares       1,000            
Board of Directors [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period   2 years                
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross   189,873                
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share) | $ / shares   $ 4.66                
Share Based Compensation Arrangement by Share Based Payment Award Options Term   5 years                
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share) | $ / shares   $ 1.65                
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term   3 years 3 months                
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate   48.60%                
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate   1.31%                
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Payments (in Dollars) | $   $ 0                
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares   126,582                
Executive Officers [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period           3 years        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross           40,000        
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share) | $ / shares           $ 3.40        
Share Based Compensation Arrangement by Share Based Payment Award Options Term           5 years        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share) | $ / shares           $ 1.39        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term           3 years 6 months        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate           55.63%        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate           1.00%        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Payments (in Dollars) | $           $ 0        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares           23,334        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares           5,000        
2005 Plan [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized           1,000,000        
Share Based Compensation Arrangement by Share Based Payment Award Number of Additional Awards to be Granted           0        
2011 Plan [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Share Based Compensation Arrangement by Share Based Payment Award Restricted Stock Units                   3,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant           350,000        
Common Stock [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Authorized Common Stock that may be Issued and Sold Under Sales Agreement (in Dollars) | $           $ 19,150,000        
Securities That May Be Sold Under The Agreement (in Dollars) | $           $ 150,000,000        
Stock Issued During Period, Shares, Employee Benefit Plan           91,541 160,352 214,984    
Payments of Stock Issuance Costs (in Dollars) | $           $ 724,000 $ 709,000 $ 662,000    
Minimum [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period           2 years        
Maximum [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period           4 years        
2011 Plan [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Number of Shares of Common Stock Remain Available for Issuance as Option for Plan Termination           0        
Restricted Stock [Member] | Common Stock [Member]                    
Stockholders' Equity (Details) [Line Items]                    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value (in Dollars) | $           $ 44,000 $ 46,000 $ 79,000