Components of Total Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2011
Schedule of Unrecognized Tax Benefits [Line Items]
Unrecognized tax benefits	$ 20,813	$ 32,733	$ 33,900	$ 32,174
Reduction to unrecognized tax benefits for tax credit carry forward	(657)	(440)
Accrued interest and penalties	5,200	11,671	13,265
Total unrecognized tax benefits	25,356	43,964	47,165
Short-term, included in "Income and other taxes"	1,667	2,745	2,649
Long-term unrecognized tax benefits	23,689	41,219	44,516
Total unrecognized tax benefits	$ 25,356	$ 43,964	$ 47,165