Note 7 - Restructuring Costs (Details Textual) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Oct. 28, 2017	Feb. 03, 2018
Asset Impairment Charges, Total		$ 50,351
Fiscal 2018 Plan [Member]
Severance Costs		9,300
Fiscal 2018 Plan [Member] \| Employee Severance [Member] \| Other Accrued Liabilities [Member]
Restructuring Reserve, Ending Balance		$ 1,600
Purchased IP and Mask Sets [Member] \| Fiscal 2018 Plan [Member]
Asset Impairment Charges, Total	$ 9,700

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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-Paragraph 1
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- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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