Inventories - Summary of Inventories (Details) - USD ($) $ in Thousands	Jul. 28, 2019	Jan. 27, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 2,271	$ 2,057
Work in progress	52,863	44,530
Finished goods	19,926	17,092
Inventories	$ 75,060	$ 63,679

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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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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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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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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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