Supplemental Operations Statement and Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Supplemental Operations Statement and Cash Flow Information [Abstract]
Advertising expenses	$ 188.6	$ 124.1	$ 93.2
Research and development expenses	29.0	22.9	18.9
Interest income	(14.8)	(20.9)	(4.4)
Interest paid	321.2	300.2	320.0
Income taxes paid	178.5	114.7	45.8
Accrued additions to property	$ 89.6	$ 37.9	$ 36.4

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Supplemental Operations Statement and Cash Flow Information [Abstract]

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Amount, before refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

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Amount of interest income earned from interest bearing assets classified as other.

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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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The total expense recognized in the period for promotion, public relations, and brand or product advertising.

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Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

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