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Income Taxes - Components of Income Tax Expense of Continuing Operations (Detail) - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2025	Aug. 31, 2024	Aug. 31, 2023
Current
Federal	$ 8.4	$ 2.0	$ 7.4
State	1.8	2.2	2.7
Foreign	35.2	38.8	9.7
Current Income Tax Expense (Benefit), Total	45.4	43.0	19.8
Deferred
Federal	47.5	14.6	7.9
State	8.2	0.1	0.6
Foreign	(7.7)	(2.0)	(3.4)
Total Deferred Income Tax Expense (Benefit)	48.0	12.7	5.1
Change in valuation allowance	(2.0)	6.3	(0.3)
Income tax expense	$ 91.4	$ 62.0	$ 24.6

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