Inventories - Components of Inventories (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Components of Inventories
Raw materials	$ 16,749us-gaap_InventoryRawMaterials	$ 14,825us-gaap_InventoryRawMaterials
Work in process	15,652us-gaap_InventoryWorkInProcess	13,168us-gaap_InventoryWorkInProcess
Inventories	$ 32,401us-gaap_InventoryNet	$ 27,993us-gaap_InventoryNet

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

-Publisher SEC

-Name Regulation S-X (SX)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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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.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

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-Section 02

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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