Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Raw materials	$ 39,810	$ 46,789
Work-in-process	32,613	28,386
Finished products	3,440	3,332
Total inventories	75,863	78,507
Less reserves	(3,188)	(3,479)
Total inventories, net	$ 72,675	$ 75,028

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

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