Income Taxes - Tax Effects of Temporary Differences that give rise to Significant Portions of Deferred Tax Assets and Deferred Tax Liabilities (Detail) - USD ($) $ in Millions	Aug. 31, 2026	Aug. 31, 2025
Deferred tax assets:
Accrued payroll and related liabilities	$ 36.7	$ 32.7
Accrued liabilities	5.6	5.2
Deferred revenue	5.3	11.2
Inventories and other	9.0	15.8
Maintenance and warranty accruals	4.4	4.8
Lease liability	17.8	18.8
Interest expense	15.8	15.5
Net operating losses	43.5	21.2
Investment, asset tax credits and other	30.4	16.3
Deferred Tax Assets, Gross, Total	168.5	141.5
Valuation allowance	(23.0)	(13.9)
Deferred tax liabilities:
Fixed assets	(260.4)	(234.3)
Intangibles	(5.8)	(3.6)
Right-of-use asset	(17.8)	(18.5)
Other	(12.2)	(9.5)
Deferred Tax Liabilities, Gross, Total	(296.2)	(265.9)
Net deferred tax liability	$ (150.7)	$ (138.3)

Deferred tax assets, interest expense.

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Deferred tax assets, investment, asset tax credits and other.

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Deferred tax assets, lease liability.

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Deferred tax assets, tax deferred expense, reserves and accruals, accrued payroll and related liabilities.

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from warranty reserves.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from leasing arrangements.

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Amount of deferred tax liability attributable to taxable temporary differences classified as other.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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