Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 28, 2017	Oct. 29, 2016	Oct. 28, 2017	Oct. 29, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 359	$ 8,780	$ (1,497)	$ 16,307
Unrealized (loss) gain on available-for-sale investments	(22)	0	12	0
Cumulative translation adjustment	7	(2)	(10)	(5)
Comprehensive income (loss), net of tax	$ 344	$ 8,778	$ (1,495)	$ 16,302

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831270

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=51831223

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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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 before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, on foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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