Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 29, 2017	Jul. 30, 2016	Jul. 29, 2017	Jul. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 2,193	$ 5,109	$ (1,856)	$ 7,527
Unrealized gain on available-for-sale investments	21	0	34	0
Cumulative translation adjustment	(11)	(8)	(17)	(3)
Comprehensive income (loss), net of tax	$ 2,203	$ 5,101	$ (1,839)	$ 7,524

Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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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.

+ References

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
-Glossary Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831223

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=51831255

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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-Paragraph 1
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-Name Accounting Standards Codification
-Topic 942
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-Paragraph 1
-Subparagraph (SX 210.9-04(22))
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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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