The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 34
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An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date(s) more than one year from the balance sheet date. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Note 4 - Investments in Privately-held Companies (Details Textual) - USD ($) $ in Millions	3 Months Ended					12 Months Ended
	Apr. 30, 2016	Jan. 30, 2016	Oct. 29, 2011	Oct. 30, 2010	Jan. 30, 2010	Jan. 31, 2009	Nov. 30, 2010
Issuer A [Member] \| Preferred Stock Investments [Member]
Payments to Acquire Investments					$ 1.0	$ 1.0
Issuer A [Member]
Notes, Loans and Financing Receivable, Gross, Noncurrent							$ 1.0
Issuer B [Member] \| Preferred Stock Investments [Member]
Payments to Acquire Investments				$ 1.0
Other than Temporary Impairment Losses, Investments	$ 0.3	$ 0.3
Issuer D [Member]
Payments to Acquire Investments			$ 0.1