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Inventories - Components of Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Short-term inventories:
Raw materials	$ 53,472	$ 52,598
Work-in-process	2,057	4,902
Finished goods	19,406	49,351
Supplies	2,337	3,541
Total short-term inventories	77,272	110,392
Long-term inventories:
Finished goods	1,398	1,249
Total inventories	$ 78,670	$ 111,641

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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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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of products used directly or indirectly in the manufacturing or production process, which may or may not become part of the final product. May also include items used in the storage, presentation or transportation of physical goods.

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