Concentration Risk, Minimum Concentration Risk Threshold, Percentage

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- Definition

Number Of Customers Accounting For At Least Ten Percent Of Net Receivables

+ References

No definition available.

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- Definition

Description of risks that arise due to concentrations of operating facilities, revenues, assets, customers, vendors or the like in a certain geographic area, either domestic or foreign. The description may address risks inherent in the geographic area, and, at a minimum, informs users of the general nature of the risk, but excludes "Information about Geographic Areas" that may be disclosed elsewhere (for instance, segment disclosures)..

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6327-108592

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

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Concentration of Risk - Narrative (Details) - Customers	3 Months Ended		6 Months Ended
Concentration of Risk - Narrative (Details) - Customers	Jul. 30, 2017	Jul. 31, 2016	Jul. 30, 2017	Jul. 31, 2016	Jan. 29, 2017
Concentration Risk [Line Items]
Number of customers accounting for at least 10% of total net receivables	0		0		0
Description of geographic concentration risk related to distributors	For the second quarter of fiscal year 2018, our two largest distributors were based in Asia.
Sales Revenue, Goods, Net [Member]
Concentration Risk [Line Items]
Minimum concentration risk threshold	10.00%		10.00%
Concentration risk, percentage	100.00%	100.00%	100.00%	100.00%
Accounts Receivable [Member]
Concentration Risk [Line Items]
Minimum concentration risk threshold	10.00%
Net sales [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	100.00%	100.00%	100.00%	100.00%
Net sales [Member] \| Distributor concentration risk [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	65.00%	64.00%
China \| Cost of Silicon Wafers [Member] \| Supplier concentration risk [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	21.00%	24.00%