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Goodwill - Schedule of Changes in Carrying Value of Goodwill (Detail) $ in Thousands	12 Months Ended
	Aug. 31, 2021 USD ($)
Goodwill [Line Items]
Beginning balance	$ 130,308
Translation and other adjustments	1,802
Ending balance	132,110
Gross goodwill balance before accumulated goodwill impairment losses and other reductions	294,660
Accumulated goodwill impairment losses	(138,234)
Accumulated other reductions	(24,316)
Manufacturing
Goodwill [Line Items]
Beginning balance	87,043
Translation and other adjustments	1,802
Ending balance	88,845
Wheels, Repair & Parts
Goodwill [Line Items]
Beginning balance	43,265
Ending balance	$ 43,265

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Goodwill, accumulated impairment losses and other reductions.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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