Accumulated Other Comprehensive (Loss) Income (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2017	Jan. 31, 2016
Components and changes in accumulated other comprehensive (loss) income
Balance			$ 454,370,000
Balance	$ 483,160,000		483,160,000
Accumulated Other Comprehensive Income
Components and changes in accumulated other comprehensive (loss) income
Balance	(18,316,000)	$ 397,000	(11,795,000)	$ 1,224,000
Balance	(15,728,000)	(6,802,000)	(15,728,000)	(6,802,000)
Foreign Currency Translation Adjustments
Components and changes in accumulated other comprehensive (loss) income
Other comprehensive loss for foreign currency translation	$ 2,588,000	$ (7,199,000)	$ (3,933,000)	$ (8,026,000)