Components of Inventories (Detail) (USD $) In Thousands, unless otherwise specified	May 31, 2013	Aug. 31, 2012
Inventory Disclosure [Line Items]
Manufacturing supplies and raw materials	$ 221,767	$ 228,092
Work-in-process	74,303	71,210
Finished goods	53,366	22,571
Excess and obsolete adjustment	(5,268)	(5,132)
Inventories	$ 344,168	$ 316,741

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Certain changes made in the current period to the value and amount of inventory reported.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Section A

-Paragraph 9

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Amount before last-in first-out (LIFO) and valuation reserves of merchandise or goods held by the entity that are readily available for sale.

+ References

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-Publisher SEC

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Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

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- Definition

Gross amount of unprocessed items to be consumed in the manufacturing or production process. Also includes purchased parts that will be used as components of a finished product.

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Gross amount of merchandise or goods which are partially completed, are generally comprised of raw materials, labor and factory overhead costs, and 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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