Inventories - Components of Inventories (Detail) - USD ($) $ in Thousands	Aug. 31, 2018	Aug. 31, 2017
Inventory [Line Items]
Manufacturing supplies and raw materials	$ 278,726	$ 222,080
Work-in-process	105,021	86,794
Finished goods	54,181	95,389
Excess and obsolete adjustment	(5,614)	(4,136)
Inventories	$ 432,314	$ 400,127

Amount of inventory reserves for last-in first-out (LIFO) and other inventory valuation methods.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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