Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Topic 320
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Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

+ 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=6505594

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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No definition available.

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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-Subparagraph (bb)
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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Trading Securities
-URI http://asc.fasb.org/extlink&oid=6526789

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 25
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Available-for-Sale Securities
-URI http://asc.fasb.org/extlink&oid=6505594

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 1
-Subparagraph a, f, g
-Article 7

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Fair Value Measurements-recurring (Details) - Recurring basis - USD ($) $ in Thousands	Jan. 30, 2016	Jan. 31, 2015
Fair value measurements
Total assets	$ 3,015	$ 18,045
Level 1 to Level 2 Transfers	0
Level 2 to Level 1 Transfers	0
Level 2
Fair value measurements
Total assets	3,015	18,045
Short Term Investments
Fair value measurements
Short-term investments		13,293
Short Term Investments \| Certificates of deposit
Fair value measurements
Short-term investments		4,078
Short Term Investments \| Commercial paper
Fair value measurements
Short-term investments		7,384
Short Term Investments \| Corporate bonds
Fair value measurements
Short-term investments	2,810	1,616
Short Term Investments \| Municipal bonds
Fair value measurements
Short-term investments	205
Short Term Investments \| U.S. Agency securities
Fair value measurements
Short-term investments		215
Short Term Investments \| Level 2
Fair value measurements
Short-term investments		13,293
Short Term Investments \| Level 2 \| Certificates of deposit
Fair value measurements
Short-term investments		4,078
Short Term Investments \| Level 2 \| Commercial paper
Fair value measurements
Short-term investments		7,384
Short Term Investments \| Level 2 \| Corporate bonds
Fair value measurements
Short-term investments	2,810	1,616
Short Term Investments \| Level 2 \| Municipal bonds
Fair value measurements
Short-term investments	$ 205
Short Term Investments \| Level 2 \| U.S. Agency securities
Fair value measurements
Short-term investments		215
Long-term investments
Fair value measurements
Long-term investments		4,752
Long-term investments \| Corporate bonds
Fair value measurements
Long-term investments		2,853
Long-term investments \| U.S. Agency securities
Fair value measurements
Long-term investments		1,899
Long-term investments \| Level 2
Fair value measurements
Long-term investments		4,752
Long-term investments \| Level 2 \| Corporate bonds
Fair value measurements
Long-term investments		2,853
Long-term investments \| Level 2 \| U.S. Agency securities
Fair value measurements
Long-term investments		$ 1,899