Inventories - Summary of Inventories (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Inventory Disclosure [Abstract]
Finished goods	$ 13,737	$ 7,867
Semi-finished goods and work-in-process	53,148	46,653
Raw materials	12,445	7,846
Materials in-transit	134	1,859
Less: inventory reserve	(6,391)	(7,177)	$ (16,033)	$ (47,488)
Inventories, net	$ 73,073	$ 57,048

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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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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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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Amount of valuation reserve for inventory.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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Gross amount of merchandise or supplies to which the entity holds the title but does not hold physical possession because the goods are currently being transported.

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