Inventories - Components of Inventories (Detail) - USD ($) $ in Millions	Feb. 29, 2024	Aug. 31, 2023
Inventory Disclosure [Abstract]
Manufacturing supplies and raw materials	$ 600.1	$ 638.2
Work-in-process	133.1	138.2
Finished goods	99.7	64.4
Excess and obsolete adjustment	(5.9)	(17.2)
Inventories	$ 827.0	$ 823.6

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 1
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- Definition

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

+ References

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- Definition

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/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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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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