CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY Statement - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]
Beginning balance at Jan. 27, 2018	$ 724,996	$ 10,395	$ 6,170	$ (1,146)	$ 709,577
Beginning balance (shares) at Jan. 27, 2018		31,185,669
Increase (Decrease) in Stockholders' Equity
Stock options exercised	501	$ 16	485
Stock options exercised (shares)		45,217
Stock-based compensation	18,277	$ 0	18,277
Stock-based compensation (shares)		2,015
Issuance of restricted stock, net of tax withholdings	(1,750)	$ 17	(1,767)
Issuance of restricted stock, net of tax withholdings (shares)		50,510
Other comprehensive loss	(127)			(127)
Net income	74,961				74,961
Ending balance at Oct. 27, 2018	816,858	$ 10,428	23,165	(1,273)	784,538
Ending balance (shares) at Oct. 27, 2018		31,283,411
Beginning balance at Jul. 28, 2018	783,205	$ 10,408	17,356	(1,267)	756,708
Beginning balance (shares) at Jul. 28, 2018		31,224,470
Increase (Decrease) in Stockholders' Equity
Stock options exercised	120	$ 4	116
Stock options exercised (shares)		10,775
Stock-based compensation	7,366	$ 0	7,366
Stock-based compensation (shares)		925
Issuance of restricted stock, net of tax withholdings	(1,657)	$ 16	(1,673)
Issuance of restricted stock, net of tax withholdings (shares)		47,241
Other comprehensive loss	(6)			(6)
Net income	27,830				27,830
Ending balance at Oct. 27, 2018	816,858	$ 10,428	23,165	(1,273)	784,538
Ending balance (shares) at Oct. 27, 2018		31,283,411
Beginning balance at Jan. 26, 2019	$ 804,168	$ 10,477	22,489	(1,282)	772,484
Beginning balance (shares) at Jan. 26, 2019	31,430,031	31,430,031
Increase (Decrease) in Stockholders' Equity
Stock options exercised	$ 313	$ 9	304
Stock options exercised (shares)		26,479
Stock-based compensation	8,450	$ 0	8,450
Stock-based compensation (shares)		4,538
Issuance of restricted stock, net of tax withholdings	(1,182)	$ 21	(1,203)
Issuance of restricted stock, net of tax withholdings (shares)		59,437
Other comprehensive loss	(3)			(3)
Net income	68,404				68,404
Ending balance at Oct. 26, 2019	$ 880,150	$ 10,507	30,040	(1,285)	840,888
Ending balance (shares) at Oct. 26, 2019	31,520,485	31,520,485
Beginning balance at Jul. 27, 2019	$ 853,433	$ 10,496	27,563	(1,285)	816,659
Beginning balance (shares) at Jul. 27, 2019		31,489,923
Increase (Decrease) in Stockholders' Equity
Stock options exercised	130	$ 3	127
Stock options exercised (shares)		9,609
Stock-based compensation	2,694	$ 0	2,694
Stock-based compensation (shares)		1,301
Issuance of restricted stock, net of tax withholdings	(336)	$ 8	(344)
Issuance of restricted stock, net of tax withholdings (shares)		19,652
Other comprehensive loss	0			0
Net income	24,229				24,229
Ending balance at Oct. 26, 2019	$ 880,150	$ 10,507	$ 30,040	$ (1,285)	$ 840,888
Ending balance (shares) at Oct. 26, 2019	31,520,485	31,520,485

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The number of restricted shares issued as compensation, net of shares for the payment of withholding taxes. This element is to be used only if shares are used in lieu of cash to satisfy all or a portion of withholding taxes.

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The value of restricted shares issued as compensation, net of the value of shares for the payment of withholding taxes. This element is to be used only if shares are used in lieu of cash to satisfy all or a portion of withholding taxes.

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Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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