Inventories - Summary of Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Inventories
Finished goods	$ 7,247	$ 10,995
Work-in-process	14,835	12,129
Raw materials	26,197	25,746
Less: Inventory reserves	(5,125)	(5,384)
Inventories, net	$ 43,154	$ 43,486

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.

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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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