The charge against earnings resulting from the aggregate write down of all assets from their carrying value to their fair value.

+ References+ Details

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.

+ References

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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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

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-Paragraph 4, 5

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+ Details

- Definition

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 Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

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-Glossary Available-for-Sale Securities

-URI http://asc.fasb.org/extlink&oid=6505594

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+ Details

Fair Value Measurements (Details 2) (USD $)	6 Months Ended
Fair Value Measurements (Details 2) (USD $)	Aug. 03, 2013	Jul. 28, 2012	Feb. 02, 2013	Apr. 28, 2012
Fair value measurements
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	$ 0			$ 0
Short-term investments	5,050,000		0
Carrying amount of long-lived assets held and used	100,000			200,000
Fair value of long-lived assets held and used	0			0
Asset Impairment Charges	100,000	100,000
Fair Value, Measurements, Recurring [Member]
Fair value measurements
Assets, Fair Value Disclosure	9,830,000
Fair Value, Measurements, Recurring [Member] \| Level 1
Fair value measurements
Assets, Fair Value Disclosure	0
Fair Value, Measurements, Recurring [Member] \| Level 2
Fair value measurements
Assets, Fair Value Disclosure	9,830,000
Fair Value, Measurements, Recurring [Member] \| Level 3
Fair value measurements
Assets, Fair Value Disclosure	0
Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member]
Fair value measurements
Available-for-sale Securities, Noncurrent	4,780,000
Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 1
Fair value measurements
Available-for-sale Securities, Noncurrent	0
Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 2
Fair value measurements
Available-for-sale Securities, Noncurrent	4,780,000
Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 3
Fair value measurements
Available-for-sale Securities, Noncurrent	0
Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member]
Fair value measurements
Available-for-sale Securities, Current	5,050,000
Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 1
Fair value measurements
Available-for-sale Securities, Current	0
Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 2
Fair value measurements
Available-for-sale Securities, Current	5,050,000
Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 3
Fair value measurements
Available-for-sale Securities, Current	0
Certificates of Deposit [Member] \| Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member]
Fair value measurements
Available-for-sale Securities, Current	2,268,000
Certificates of Deposit [Member] \| Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 1
Fair value measurements
Available-for-sale Securities, Current	0
Certificates of Deposit [Member] \| Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 2
Fair value measurements
Available-for-sale Securities, Current	2,268,000
Certificates of Deposit [Member] \| Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 3
Fair value measurements
Available-for-sale Securities, Current	0
Commercial Paper [Member] \| Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member]
Fair value measurements
Available-for-sale Securities, Current	2,374,000
Commercial Paper [Member] \| Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 1
Fair value measurements
Available-for-sale Securities, Current	0
Commercial Paper [Member] \| Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 2
Fair value measurements
Available-for-sale Securities, Current	2,374,000
Commercial Paper [Member] \| Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 3
Fair value measurements
Available-for-sale Securities, Current	0
US Government Agencies Debt Securities [Member] \| Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member]
Fair value measurements
Available-for-sale Securities, Noncurrent	2,069,000
US Government Agencies Debt Securities [Member] \| Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 1
Fair value measurements
Available-for-sale Securities, Noncurrent	0
US Government Agencies Debt Securities [Member] \| Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 2
Fair value measurements
Available-for-sale Securities, Noncurrent	2,069,000
US Government Agencies Debt Securities [Member] \| Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 3
Fair value measurements
Available-for-sale Securities, Noncurrent	0
US Government Agencies Debt Securities [Member] \| Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member]
Fair value measurements
Available-for-sale Securities, Current	408,000
US Government Agencies Debt Securities [Member] \| Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 1
Fair value measurements
Available-for-sale Securities, Current	0
US Government Agencies Debt Securities [Member] \| Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 2
Fair value measurements
Available-for-sale Securities, Current	408,000
US Government Agencies Debt Securities [Member] \| Short-term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 3
Fair value measurements
Available-for-sale Securities, Current	0
Municipal Bonds [Member] \| Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member]
Fair value measurements
Available-for-sale Securities, Noncurrent	227,000
Municipal Bonds [Member] \| Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 1
Fair value measurements
Available-for-sale Securities, Noncurrent	0
Municipal Bonds [Member] \| Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 2
Fair value measurements
Available-for-sale Securities, Noncurrent	227,000
Municipal Bonds [Member] \| Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 3
Fair value measurements
Available-for-sale Securities, Noncurrent	0
Corporate Bond Securities [Member] \| Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member]
Fair value measurements
Available-for-sale Securities, Noncurrent	2,484,000
Corporate Bond Securities [Member] \| Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 1
Fair value measurements
Available-for-sale Securities, Noncurrent	0
Corporate Bond Securities [Member] \| Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 2
Fair value measurements
Available-for-sale Securities, Noncurrent	2,484,000
Corporate Bond Securities [Member] \| Long Term Investments [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 3
Fair value measurements
Available-for-sale Securities, Noncurrent	$ 0