Income Taxes (Details 4) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015
Schedule Of Deferred Tax Assets (Liabilities) [Line Items]
Net deferred tax (liabilities) assets	$ (1,997)	$ 21,134
UNITED STATES
Schedule Of Deferred Tax Assets (Liabilities) [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Domestic	385,526	339,013	$ 286,169
U.S. current (liabilities) assets	(92)	1,444
U.S. non-current assets	1,054	23,506
International [Member]
Schedule Of Deferred Tax Assets (Liabilities) [Line Items]
International non-current liabilities	(2,959)	(3,816)
Income (Loss) from Continuing Operations before Income Taxes, Foreign	$ 54,574	$ 56,852	$ 45,900