Note 5 - Software, Equipment and Leasehold Improvements (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 30, 2016	Jan. 30, 2016
Software and Software Development Costs [Member]
Estimated Useful Lives	2 years
Property, plant, and equipment, gross	$ 40,697	$ 40,411
Mask Sets [Member] \| Minimum [Member]
Estimated Useful Lives	1 year
Mask Sets [Member] \| Maximum [Member]
Estimated Useful Lives	5 years
Mask Sets [Member]
Property, plant, and equipment, gross	$ 14,460	14,130
Equipment [Member] \| Minimum [Member]
Estimated Useful Lives	1 year
Equipment [Member] \| Maximum [Member]
Estimated Useful Lives	5 years
Equipment [Member]
Property, plant, and equipment, gross	$ 8,261	8,088
Office Equipment [Member]
Estimated Useful Lives	2 years
Property, plant, and equipment, gross	$ 7,875	7,705
Leasehold Improvements [Member] \| Minimum [Member]
Estimated Useful Lives	1 year
Leasehold Improvements [Member] \| Maximum [Member]
Estimated Useful Lives	6 years
Leasehold Improvements [Member]
Property, plant, and equipment, gross	$ 2,115	2,089
Property, plant, and equipment, gross	73,408	72,423
Less: Accumulated depreciation and amortization	(61,888)	(58,337)
Total software, equipment and leasehold improvements, net	$ 11,520	$ 14,086

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
-Topic 360
-SubTopic 10
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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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)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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+ 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

Reference 2: 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(14))
-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))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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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