Components of Total Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Schedule of Unrecognized Tax Benefits [Line Items]
Unrecognized tax benefits	$ 13,269	$ 13,156	$ 20,813	$ 32,733
Reduction to unrecognized tax benefits for tax credit carry forward	(2,255)	(2,109)	(657)
Accrued interest and penalties	1,547	1,895	5,200
Total unrecognized tax benefits	12,561	12,942	25,356
Short-term, included in "Income and other taxes"	2,586	997	1,667
Long-term	9,975	11,945	23,689
Total unrecognized tax benefits	$ 12,561	$ 12,942	$ 25,356