Inventories - Inventories, Net of Reserves (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Inventory Disclosure [Abstract]
Raw materials	$ 66,232	$ 59,440
In-process and finished	123,350	109,578
Supplies	68,250	67,292
Total	$ 257,832	$ 236,310

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Amount before valuation reserves of merchandise or goods held by the entity that are readily available for sale and items held by the entity which are partially complete or in the process of being readied 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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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer.

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