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Goodwill - Schedule of Changes in Carrying Value of Goodwill (Detail) $ in Millions	12 Months Ended
	Aug. 31, 2024 USD ($)
Goodwill [Line Items]
Beginning balance	$ 128.9
Translation and other adjustments	0.4
Gross goodwill balance before accumulated goodwill impairment losses and other reductions	292.3
Accumulated goodwill impairment losses	(138.2)
Accumulated other reductions	(25.6)
Ending balance	128.5
Manufacturing
Goodwill [Line Items]
Beginning balance	85.9
Ending balance	85.9
Maintenance Services
Goodwill [Line Items]
Beginning balance	43.0
Translation and other adjustments	(0.4)
Ending balance	$ 42.6

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