Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity (Details)

v3.8.0.1
Stockholders' Equity (Details) - USD ($)
 6 Months Ended
Jan. 31, 2018
Jan. 31, 2017
Jul. 31, 2017
Dec. 31, 2014
Stockholders' Equity (Details) [Line Items]        
Common Stock, Par or Stated Value Per Share (in Dollars per share) $ 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, Exercises in Period (in Shares) 569,602      
Excess Tax Benefit from Share-based Compensation, Financing Activities $ 0 $ 0    
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options $ 1,000,000      
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition 15 months      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value $ 21,000 $ 8,000    
Officer [Member]        
Stockholders' Equity (Details) [Line Items]        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in Shares) 340,898      
Treasury Stock, Shares, Acquired (in Shares) 106,911      
Treasury Stock, Value, Acquired, Cost Method $ 1,014,000      
2011 Plan [Member]        
Stockholders' Equity (Details) [Line Items]        
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares) 5,000,000   3,000,000  
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares) 2,263,400      
Common Stock [Member]        
Stockholders' Equity (Details) [Line Items]        
Authorized Common Stock That May Be Issued And Sold Under Sales Agreement $ 19,150,000      
Securities That May Be Sold Under The Agreement $ 150,000,000      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in Shares) 228,704      
Treasury Stock, Shares, Acquired (in Shares) 340,898      
Restricted Stock [Member]        
Stockholders' Equity (Details) [Line Items]        
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options $ 100,000      
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Outstanding Weighted Average Remaining Contractual Terms 22 months