Stock-Based Compensation (Details) (Stock Options, USD $)
In Thousands, except Per Share data, unless otherwise specified
9 Months Ended 12 Months Ended
Apr. 30, 2013
Jul. 31, 2012
Stock Options
   
Share-based Compensation Arrangement by Share-based Payment Award    
Options Outstanding, Number (shares) 79 147
Options, Outstanding, Weighted Average Exercise Price $ 13.49 $ 11.89
Options, Outstanding, Weighted Average Remaining Contractual Term (years) 2 years 2 months 12 days 2 years 2 months 12 days
Options, Outstanding, Aggregate Intrinsic Value $ 1,101 $ 1,473
Exercised, Number (shares) (68)  
Exercised, Weighted Average Exercise Price $ 10.05  
Exercised, Aggregate Intrinsic Value 1,053  
Options Exercisable, Number (shares) 79  
Exercisable, Weighted Average Exercise Price $ 13.49  
Exercisable, Weighted Average Remaining Contractual Term (years) 2 years 2 months 12 days  
Exercisable, Aggregate Intrinsic Value $ 1,101