Note 5 - Intangible Assets - Acquired Intangible Assets, Subject to Amortization (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jul. 29, 2017	Jan. 28, 2017
Gross value	$ 199,134	$ 196,466
Impairment	(68,062)	(65,056)
Accumulated amortization and effect of currency translation	(103,873)	(100,666)
Finite-Lived Intangible Assets, Net	$ 27,199	$ 30,744
Developed Technology Rights [Member]
Weighted average remaining amortization period (Year)	7 years 73 days	7 years 146 days
Gross value	$ 85,427	$ 85,427
Impairment	(24,614)	(24,614)
Accumulated amortization and effect of currency translation	(53,675)	(52,854)
Finite-Lived Intangible Assets, Net	$ 7,138	$ 7,959
Customer Relationships [Member]
Weighted average remaining amortization period (Year)	5 years 109 days	5 years 292 days
Gross value	$ 54,505	$ 54,505
Impairment	(30,486)	(30,486)
Accumulated amortization and effect of currency translation	(21,169)	(20,897)
Finite-Lived Intangible Assets, Net	$ 2,850	$ 3,122
Trademarks and Other [Member]
Weighted average remaining amortization period (Year)	1 year 109 days	1 year 328 days
Gross value	$ 4,078	$ 4,078
Impairment
Accumulated amortization and effect of currency translation	(3,918)	(3,858)
Finite-Lived Intangible Assets, Net	$ 160	$ 220
Purchased IP-Amortizing [Member]
Weighted average remaining amortization period (Year)	2 years	2 years 109 days
Gross value	$ 35,978	$ 36,007
Impairment	(5,516)	(5,516)
Accumulated amortization and effect of currency translation	(25,111)	(23,057)
Finite-Lived Intangible Assets, Net	$ 5,351	$ 7,434
Acquired Intangible Assets Subtotal [Member]
Weighted average remaining amortization period (Year)	5 years	5 years
Gross value	$ 179,988	$ 180,017
Impairment	(60,616)	(60,616)
Accumulated amortization and effect of currency translation	(103,873)	(100,666)
Finite-Lived Intangible Assets, Net	15,499	18,735
Purchased Intellectual Property - Not Yet Deployed [Member]
Gross value	19,146	16,449
Impairment	(7,446)	(4,440)
Accumulated amortization and effect of currency translation
Finite-Lived Intangible Assets, Net	$ 11,700	$ 12,009

The accumulated impairment losses related to intangible assets as of the balance sheet date.

No definition available.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

+ Details

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

No definition available.

+ Details

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