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	381	$ 12	369
Stock options exercised (shares)		34,442
Stock-based compensation	10,911	$ 0	10,911
Stock-based compensation (shares)		1,090
Issuance of restricted stock, net of tax withholdings	(93)	$ 1	(94)
Issuance of restricted stock, net of tax withholdings (shares)		3,269
Other comprehensive loss	(121)			(121)
Net income	47,131				47,131
Ending balance at Jul. 28, 2018	783,205	$ 10,408	17,356	(1,267)	756,708
Ending balance (shares) at Jul. 28, 2018		31,224,470
Beginning balance at Apr. 28, 2018	746,982	$ 10,398	11,010	(1,234)	726,808
Beginning balance (shares) at Apr. 28, 2018		31,193,069
Increase (Decrease) in Stockholders' Equity
Stock options exercised	314	$ 10	304
Stock options exercised (shares)		29,358
Stock-based compensation	6,048	$ 0	6,048
Stock-based compensation (shares)		666
Issuance of restricted stock, net of tax withholdings	(6)	$ 0	(6)
Issuance of restricted stock, net of tax withholdings (shares)		1,377
Other comprehensive loss	(33)			(33)
Net income	29,900				29,900
Ending balance at Jul. 28, 2018	783,205	$ 10,408	17,356	(1,267)	756,708
Ending balance (shares) at Jul. 28, 2018		31,224,470
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	$ 182	$ 5	177
Stock options exercised (shares)		16,870
Stock-based compensation	5,756	$ 2	5,754
Stock-based compensation (shares)		3,237
Issuance of restricted stock, net of tax withholdings	(845)	$ 12	(857)
Issuance of restricted stock, net of tax withholdings (shares)		39,785
Other comprehensive loss	(3)			(3)
Net income	44,175				44,175
Ending balance at Jul. 27, 2019	$ 853,433	$ 10,496	27,563	(1,285)	816,659
Ending balance (shares) at Jul. 27, 2019	0	31,489,923
Beginning balance at Apr. 27, 2019	$ 821,177	$ 10,493	25,217	(1,296)	786,763
Beginning balance (shares) at Apr. 27, 2019		31,478,851
Increase (Decrease) in Stockholders' Equity
Stock options exercised	76	$ 2	74
Stock options exercised (shares)		7,020
Stock-based compensation	2,277	$ 1	2,276
Stock-based compensation (shares)		1,709
Issuance of restricted stock, net of tax withholdings	(4)	$ 0	(4)
Issuance of restricted stock, net of tax withholdings (shares)		2,343
Other comprehensive loss	11			11
Net income	29,896				29,896
Ending balance at Jul. 27, 2019	$ 853,433	$ 10,496	$ 27,563	$ (1,285)	$ 816,659
Ending balance (shares) at Jul. 27, 2019	0	31,489,923

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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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