Inventories (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Inventory Disclosure [Abstract]
Raw materials	$ 7,292us-gaap_InventoryRawMaterials	$ 8,465us-gaap_InventoryRawMaterials
Work in progress	4,628us-gaap_InventoryWorkInProcess	6,126us-gaap_InventoryWorkInProcess
Finished goods	3,770us-gaap_InventoryFinishedGoods	4,800us-gaap_InventoryFinishedGoods
Supplies	927us-gaap_OtherInventorySupplies	915us-gaap_OtherInventorySupplies
Total Inventories	16,617us-gaap_InventoryGross	20,306us-gaap_InventoryGross
Inventory reserve	(132)us-gaap_InventoryValuationReserves	(131)us-gaap_InventoryValuationReserves
Net Inventories	$ 16,485us-gaap_InventoryNet	$ 20,175us-gaap_InventoryNet

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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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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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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 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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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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