CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings
Balances (in shares) at Jul. 28, 2012		33,587,744
Balances at Jul. 28, 2012	$ 392,931	$ 11,196	$ 114,820	$ 138	$ 266,777
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised (in shares)		544,162
Stock options exercised	5,253	$ 181	5,072
Non-cash stock-based compensation expense (in shares)		5,674
Stock-based compensation	9,902	$ 2	9,900
Issuance of restricted stock, net of tax withholdings (in shares)		173,537
Issuance of restricted stock, net of tax withholdings	$ (884)	$ 58	(942)
Repurchase of common stock (in shares)	(1,047,000)	(1,047,000)
Repurchase of common stock	$ (15,203)	$ (349)	(14,854)
Other comprehensive loss	(35)			(35)
Tax benefits from stock-based compensation	1,209		1,209
Net income	35,188				35,188
Balances (in shares) at Jul. 27, 2013		33,264,117
Balances at Jul. 27, 2013	428,361	$ 11,088	115,205	103	301,965
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised (in shares)		803,796
Stock options exercised	14,568	$ 268	14,300
Non-cash stock-based compensation expense (in shares)		3,999
Stock-based compensation	12,596	$ 1	12,595
Issuance of restricted stock, net of tax withholdings (in shares)		279,577
Issuance of restricted stock, net of tax withholdings	$ (3,781)	$ 93	(3,874)
Repurchase of common stock (in shares)	(360,900)	(360,900)
Repurchase of common stock	$ (9,999)	$ (120)	(9,879)
Other comprehensive loss	(261)			(261)
Tax benefits from stock-based compensation	3,472		3,472
Net income	$ 39,978				39,978
Balances (in shares) at Jul. 26, 2014	33,990,589	33,990,589
Balances at Jul. 26, 2014	$ 484,934	$ 11,330	131,819	(158)	341,943
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised (in shares)		735,330
Stock options exercised	8,922	$ 245	8,677
Non-cash stock-based compensation expense (in shares)		4,062
Stock-based compensation	13,923	$ 1	13,922
Issuance of restricted stock, net of tax withholdings (in shares)		321,722
Issuance of restricted stock, net of tax withholdings	$ (4,711)	$ 107	(4,818)
Repurchase of common stock (in shares)	(1,669,924)	(1,669,924)
Repurchase of common stock	$ (87,146)	$ (556)	(86,590)
Other comprehensive loss	(1,040)			(1,040)
Tax benefits from stock-based compensation	7,994		7,994
Net income	$ 84,324				84,324
Balances (in shares) at Jul. 25, 2015	33,381,779	33,381,779
Balances at Jul. 25, 2015	$ 507,200	$ 11,127	$ 71,004	$ (1,198)	$ 426,267