Inventories (Details) (USD $) In Thousands, unless otherwise specified	Jun. 28, 2014	Dec. 28, 2013
Inventory Disclosure [Abstract]
Raw materials	$ 41,110	$ 31,864
Work-in-process	21,285	16,880
Finished goods	58,538	57,983
Supplies and other	137	118
LIFO reserve	(13,069)	(13,626)
Inventories	$ 108,001	$ 93,219

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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 of difference between inventory at lower of LIFO cost or market and inventory at lower of other inventory accounting method cost or market, for example, but not limited to, FIFO or average cost.

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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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Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer.

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