Note 6 - Supplemental Financial Information - Software, Equipment and Leasehold Improvements (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 28, 2017	Jan. 30, 2016
Property, plant, and equipment, gross	$ 85,808	$ 72,423
Less: Accumulated depreciation and amortization	(67,285)	(58,337)
Total software, equipment and leasehold improvements, net	$ 18,523	14,086
Minimum [Member]
Property, Plant and Equipment, Useful Life	1 year
Maximum [Member]
Property, Plant and Equipment, Useful Life	5 years
Software and Software Development Costs [Member]
Property, Plant and Equipment, Useful Life
Property, plant, and equipment, gross	$ 49,915	40,411
Software and Software Development Costs [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life	3 years
Software and Software Development Costs [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life	5 years
Mask Sets [Member]
Property, Plant and Equipment, Useful Life	3 years
Property, plant, and equipment, gross	$ 18,209	14,130
Mask Sets [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life
Mask Sets [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life
Equipment [Member]
Property, Plant and Equipment, Useful Life	3 years
Property, plant, and equipment, gross	$ 7,719	8,088
Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life
Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life
Office Equipment [Member]
Property, Plant and Equipment, Useful Life
Property, plant, and equipment, gross	$ 7,857	7,705
Office Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life	3 years
Office Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life	5 years
Leasehold Improvements [Member]
Property, plant, and equipment, gross	$ 2,108	$ 2,089
Leasehold Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life	1 year
Leasehold Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life	5 years

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(13))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Topic 210
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(8))
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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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