Inventories - Components of Inventories (Detail) - USD ($) $ in Millions	Aug. 31, 2022	Aug. 31, 2021
Inventory Disclosure [Abstract]
Manufacturing supplies and raw materials	$ 570.2	$ 352.8
Work-in-process	183.3	167.3
Finished goods	75.9	73.4
Excess and obsolete adjustment	(14.1)	(19.9)
Inventories	$ 815.3	$ 573.6

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(6))
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-Section 50
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(6))
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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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