Accumulated Other Comprehensive (Loss) Income (Details) - USD ($)
3 Months Ended 6 Months Ended
Jan. 31, 2016
Jan. 31, 2015
Jan. 31, 2016
Jan. 31, 2015
Components and changes in accumulated other comprehensive (loss) income        
Balance     $ 406,633,000  
Other comprehensive loss $ (7,199,000) $ (5,609,000) (8,026,000) $ (7,500,000)
Balance 427,452,000   427,452,000  
Foreign Currency Translation Adjustments        
Components and changes in accumulated other comprehensive (loss) income        
Balance 397,000 7,661,000 1,224,000 9,552,000
Other comprehensive loss (7,199,000) (5,609,000) (8,026,000) (7,500,000)
Balance $ (6,802,000) $ 2,052,000 $ (6,802,000) $ 2,052,000