Provision for Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2016	Apr. 30, 2015
Income Tax [Line Items]
Effective income tax rate	31.90%	32.80%	32.60%	31.90%
Decreases in unrecognized tax benefits resulting from effective settlement	$ 2,891	$ 2,862	$ 2,891	$ 7,368
Income tax benefit related to gross uncertain tax benefit releases, net	1,420	1,375	1,420	3,762
Interest and penalties related to uncertain tax benefits	50	$ 92	332	385
Accrued an additional uncertain tax benefit related to prior tax periods				$ 90
Expected decrease in unrecognized tax benefits due to resolution of uncertain tax positions	$ 4,665		4,665
Expected decrease in interest due to resolution of uncertain tax positions			$ 760