Inventories - Summary of Inventories (Details) (USD $) In Thousands, unless otherwise specified	Mar. 29, 2015	Dec. 31, 2014
Inventories
Finished goods	$ 11,934us-gaap_InventoryFinishedGoods	$ 11,728us-gaap_InventoryFinishedGoods
Work-in-process	6,840us-gaap_InventoryWorkInProcess	7,297us-gaap_InventoryWorkInProcess
Raw materials	16,718us-gaap_InventoryRawMaterials	15,562us-gaap_InventoryRawMaterials
Less: Inventory reserves	(6,912)us-gaap_InventoryValuationReserves	(6,700)us-gaap_InventoryValuationReserves
Inventories, net	$ 28,580us-gaap_InventoryNet	$ 27,887us-gaap_InventoryNet

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount of valuation reserve for inventory.

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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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