Income Taxes - Components of Total Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016
Income Tax Disclosure [Abstract]
Unrecognized tax benefits	$ 13,848	$ 13,004	$ 12,671	$ 13,269
Reduction to unrecognized tax benefits which offset tax credit and loss carryforwards	(1,916)	(955)
Accrued interest and penalties	1,758	1,290
Total unrecognized tax benefits	13,690	13,339
Short-term, included in "Income and other taxes"	2,891	893
Long-term	10,799	12,446
Total unrecognized tax benefits	$ 13,690	$ 13,339