Provision for Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2017	Apr. 30, 2016
Income Tax Disclosure [Abstract]
Effective income tax rate	33.10%	31.90%	33.00%	32.60%
New accounting pronouncement or change in accounting principle, effect of change on net income	$ 0		$ 1,843
Expected decrease in unrecognized tax benefits due to resolution of uncertain tax positions	$ 5,036		5,036
Expected decrease in interest due to resolution of uncertain tax positions			$ 734