Inventories Net (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Inventory Disclosure [Abstract]
Finished products	$ 463,807	$ 433,649	$ 425,732
Products in process and raw materials	60,324	55,194	62,059
Supplies and expendable parts	113,110	110,882	112,592
Inventories, Gross	637,241	599,725	600,383
Less: Allowances	(132,364)	(130,584)	(120,527)
Total	$ 504,877	$ 469,141	$ 479,856

No definition available.

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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 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
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Amount of valuation reserve for inventory.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The aggregate carrying amount as of the balance sheet date of items held by the entity which are partially completed at the time of measurement and unprocessed items that will go through the production process and become part of the final product. Includes supplies used directly or indirectly in the manufacturing or production process. This element may be used when the reporting entity combines work in process and raw materials into an aggregate amount.

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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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-Publisher FASB
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