Income Taxes - Provision for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
Aug. 31, 2020	Aug. 31, 2019	Aug. 31, 2018
Income Tax Disclosure [Abstract]
Provision for current federal taxes	$ 54.6	$ 60.3	$ 88.9
Provision for current state taxes	12.5	14.7	16.4
Provision for current foreign taxes	16.0	10.2	9.2
(Benefit) provision for deferred taxes	(6.7)	9.3	(38.2)
Total provision for income taxes	$ 76.4	$ 94.5	$ 76.3

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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