CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 28, 2017	Jan. 23, 2016	Jan. 28, 2017	Jan. 23, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 23,663	$ 15,473	$ 74,713	$ 46,297
Foreign currency translation gains (losses), net of tax	46	(316)	20	(357)
Comprehensive income	$ 23,709	$ 15,157	$ 74,733	$ 45,940