Inventories - Summary of Inventories (Details) - USD ($) $ in Thousands	Jul. 26, 2020	Jan. 26, 2020
Inventory Disclosure [Abstract]
Raw materials	$ 2,957	$ 2,223
Work in progress	50,714	50,640
Finished goods	23,877	20,147
Inventories	$ 77,548	$ 73,010

No definition available.

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a)(1))
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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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-Publisher FASB
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-Section 45
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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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-Name Accounting Standards Codification
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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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