Note 4 - Supplemental Financial Information - Software, Equipment and Leasehold Improvements (Details) - USD ($) $ in Thousands	6 Months Ended
Jul. 29, 2017	Jan. 28, 2017
Property, plant, and equipment, gross	$ 92,818	$ 85,808
Less: Accumulated depreciation and amortization	(72,673)	(67,285)
Total software, equipment and leasehold improvements, net	20,145	18,523
Software and Software Development Costs [Member]
Property, plant, and equipment, gross	$ 51,425	49,915
Software and Software Development Costs [Member] \| Minimum [Member]
Estimated Useful Lives (Year)	3 years
Software and Software Development Costs [Member] \| Maximum [Member]
Estimated Useful Lives (Year)	5 years
Mask Sets [Member]
Property, plant, and equipment, gross	$ 22,302	18,209
Estimated Useful Lives (Year)	3 years
Equipment [Member]
Property, plant, and equipment, gross	$ 8,781	7,719
Estimated Useful Lives (Year)	3 years
Office Equipment [Member]
Property, plant, and equipment, gross	$ 8,149	7,857
Office Equipment [Member] \| Minimum [Member]
Estimated Useful Lives (Year)	3 years
Office Equipment [Member] \| Maximum [Member]
Estimated Useful Lives (Year)	5 years
Leasehold Improvements [Member]
Property, plant, and equipment, gross	$ 2,161	$ 2,108
Leasehold Improvements [Member] \| Minimum [Member]
Estimated Useful Lives (Year)	1 year
Leasehold Improvements [Member] \| Maximum [Member]
Estimated Useful Lives (Year)	5 years

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

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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