Note 5 - Supplemental Financial Information - Software, Equipment and Leasehold Improvements (Details) - USD ($) $ in Thousands	12 Months Ended
Feb. 03, 2018	May 05, 2018
Property, plant, and equipment, gross	$ 76,702	$ 35,471
Less: Accumulated depreciation and amortization	(70,524)	(35,239)
Total software, equipment and leasehold improvements, net	6,178	232
Less: Assets held for sale	(1,839)
Software, equipment and leasehold improvements, net	4,339	232
Software and Software Development Costs [Member]
Property, plant, and equipment, gross	$ 44,005	29,926
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]
Estimated Useful Lives (Year)	3 years
Property, plant, and equipment, gross	$ 14,207
Equipment [Member]
Estimated Useful Lives (Year)	3 years
Property, plant, and equipment, gross	$ 8,113	818
Office Equipment [Member]
Property, plant, and equipment, gross	$ 8,196	3,577
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	$ 2,181	$ 1,150
Leasehold Improvements [Member] \| Minimum [Member]
Estimated Useful Lives (Year)	1 year
Leasehold Improvements [Member] \| Maximum [Member]
Estimated Useful Lives (Year)	5 years

Amount after accumulated depreciation, depletion and amortization of physical assets, including assets held for sale.

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Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of, expected to be disposed of after one year or the normal operating cycle, if longer.

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