Inventories - Components of Inventories (Detail) - USD ($) $ in Millions	Feb. 28, 2022	Aug. 31, 2021
Inventory Disclosure [Abstract]
Manufacturing supplies and raw materials	$ 530.2	$ 352.8
Work-in-process	146.5	167.3
Finished goods	66.8	73.4
Excess and obsolete adjustment	(15.0)	(19.9)
Inventories	$ 728.5	$ 573.6

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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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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