Recent Accounting Pronouncements (Details) - USD ($)
3 Months Ended
Oct. 31, 2016
Oct. 31, 2015
Recent Accounting Pronouncements    
Reduction of income tax expense   $ 613,000
ASU 2016-09 Share-Based Payment Accounting | New Accounting Pronouncement, Early Adoption, Effect    
Recent Accounting Pronouncements    
Reduction of income tax expense $ 2,241,000