Inventories - Summary (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Inventory, Net [Abstract]
Raw materials	$ 36,862	$ 28,672
Work in process	18,199	29,427
Finished goods	23,840	23,901
Gross inventory total	78,901	82,000
Less: Progress billings	0	(1,661)
Total inventories	$ 78,901	$ 80,339

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section S99
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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.

+ References

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Amount, after deduction of valuation reserves, other allowances, and customer advances received on long-term contracts or programs, of inventory expected to be converted to cash, sold or exchanged within the normal operating cycle.

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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 of advances received from customers under long-term contracts which have been offset against inventories accounts at the balance sheet date.

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