CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings
Beginning balance, value at Jul. 30, 2016	$ 557,287	$ 10,473	$ 10,208	$ (1,274)	$ 537,880
Beginning balance, shares at Jul. 30, 2016		31,420,310
Increase (Decrease) in Stockholders' Equity
Stock options exercised, value	1,449	$ 34	1,415
Stock options exercised, shares		102,831
Stock-based compensation	20,805	$ 1	20,804
Stock-based compensation, shares		2,847
Issuance of restricted stock, net of tax withholdings, value	(10,767)	$ 92	(10,859)
Issuance of restricted stock, net of tax withholdings, shares		274,303
Repurchase of common stock, value	$ (62,909)	$ (238)	(19,861)		(42,810)
Repurchase of common stock, shares	(713,006)	(713,006)
Tax benefits from stock-based compensation	$ 8,385		8,385
Other comprehensive loss	116			116
Net income	157,217				157,217
Ending balance, value at Jul. 29, 2017	671,583	$ 10,362	10,092	(1,158)	652,287
Ending balance, shares at Jul. 29, 2017		31,087,285
Increase (Decrease) in Stockholders' Equity
Stock options exercised, value	745	$ 18	727
Stock options exercised, shares		52,553
Stock-based compensation	13,277	$ 1	13,276
Stock-based compensation, shares		1,492
Issuance of restricted stock, net of tax withholdings, value	(12,581)	$ 81	(7,985)		(4,677)
Issuance of restricted stock, net of tax withholdings, shares		244,339
Repurchase of common stock, value	$ (16,875)	$ (67)	(9,940)		(6,868)
Repurchase of common stock, shares	(200,000)	(200,000)
Tax benefits from stock-based compensation	$ 7,800
Other comprehensive loss	12			12
Net income	68,835				68,835
Ending balance, value at Jan. 27, 2018	724,996	$ 10,395	6,170	(1,146)	709,577
Ending balance, shares at Jan. 27, 2018		31,185,669
Increase (Decrease) in Stockholders' Equity
Stock options exercised, value	871	$ 27	844
Stock options exercised, shares		82,235
Stock-based compensation	20,187	$ 1	20,186
Stock-based compensation, shares		3,122
Issuance of restricted stock, net of tax withholdings, value	(4,657)	$ 54	(4,711)
Issuance of restricted stock, net of tax withholdings, shares		159,005
Tax benefits from stock-based compensation	200
Other comprehensive loss	(136)			(136)
Net income	62,907				62,907
Ending balance, value at Jan. 26, 2019	$ 804,168	$ 10,477	22,489	(1,282)	772,484
Ending balance, shares at Jan. 26, 2019	31,430,031	31,430,031
Increase (Decrease) in Stockholders' Equity
Stock options exercised, value	$ 503	$ 15	488
Stock options exercised, shares		45,258
Stock-based compensation	10,034		10,033
Stock-based compensation, shares		2,803
Issuance of restricted stock, net of tax withholdings, value	(1,698)	$ 35	(1,733)
Equity component of the settlement of 0.75% convertible senior notes due 2021, net of taxes	(1,206)		(1,206)
Purchase of warrants	(301)		(301)
Settlement of convertible note hedges	388		388
Issuance of restricted stock, net of tax withholdings, shares		105,846
Tax benefits from stock-based compensation	1,000
Other comprehensive loss	(499)			(499)
Net income	57,215				57,215
Ending balance, value at Jan. 25, 2020	$ 868,604	$ 10,528	$ 30,158	$ (1,781)	$ 829,699
Ending balance, shares at Jan. 25, 2020	31,583,938	31,583,938