Inventories - Summary of Inventories, at LIFO Value (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Inventory Disclosure [Abstract]
Finished goods	$ 21,655	$ 32,756
Raw materials	20,599	16,290
Total FIFO (first-in, first-out) inventories	42,254	49,046
Reserve to adjust inventories to LIFO value	(25,299)	(25,299)
Total LIFO inventories	$ 16,955	$ 23,747

No definition available.

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- Definition

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 of difference between inventory at lower of LIFO cost or market and inventory at lower of other inventory accounting method cost or market, for example, but not limited to, FIFO or average cost.

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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

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.6(a))

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 330

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-Section 35

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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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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