Inventories - Summary of Inventories (Details) (USD $) In Thousands, unless otherwise specified	Apr. 27, 2014	Jan. 26, 2014
Inventory Disclosure [Abstract]
Raw materials	$ 2,746	$ 1,971
Work in progress	35,704	45,508
Finished goods	16,846	12,788
Inventories	$ 55,296	$ 60,267

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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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