Condensed Consolidated Statements of Operations and Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Oct. 28, 2017	Oct. 29, 2016
Income Statement [Abstract]
Revenue, net	$ 295,563	$ 236,004
Cost of goods sold	166,548	125,926
Gross profit	129,015	110,078
Selling, general and administrative expenses	119,471	83,550
Operating income	9,544	26,528
Remeasurement of preferred stock warrant liability	(9,071)	1,503
Other income, net	(17)	(7)
Income before income taxes	18,632	25,032
Provision for income taxes	5,144	11,789
Net income and comprehensive income	13,488	13,243
Net income attributable to common stockholders:
Basic	3,915	3,595
Diluted	$ 1,347	$ 4,055
Earnings per share attributable to common stockholders:
Basic	$ 0.15	$ 0.15
Diluted	$ 0.04	$ 0.14
Shares used to compute earnings per share attributable to common stockholders:
Basic	26,329,495	24,349,434
Diluted	33,262,082	28,940,058