v3.25.3

Summary of Significant Accounting Policies - Other Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Finite-Lived and Indefinite-Lived, Intangible Assets
Amortization of intangible assets	$ 200.8	$ 184.6	$ 160.7
Finite-Lived Intangible Assets, Future Amortization Expense [Abstract]
2026	206.8
2027	206.8
2028	201.6
2029	190.6
2030	190.6
Finite-Lived Intangible Assets [Abstract]
Finite-Lived Intangible Assets, Gross	3,832.2	3,521.6
Finite-Lived Intangible Assets, Accumulated Amortization	(1,631.6)	(1,432.5)
Finite-Lived Intangible Assets, Net	2,200.6	2,089.1
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Carrying amount, total	4,646.2	4,578.5
Other intangible assets, net	3,014.6	3,146.0
Indefinite-lived intangible reclassification	$ 243.9
Indefinite-lived intangible assets reclassification, useful life	20 years
Customer Relationships
Finite-Lived Intangible Assets [Abstract]
Finite-Lived Intangible Assets, Gross	$ 2,699.8	2,633.3
Finite-Lived Intangible Assets, Accumulated Amortization	(1,225.3)	(1,084.1)
Finite-Lived Intangible Assets, Net	1,474.5	1,549.2
Trademarks
Finite-Lived Intangible Assets [Abstract]
Finite-Lived Intangible Assets, Gross	1,132.4	888.3
Finite-Lived Intangible Assets, Accumulated Amortization	(406.3)	(348.4)
Finite-Lived Intangible Assets, Net	726.1	539.9
Trademarks
Indefinite-lived Intangible Assets (Excluding Goodwill) [Abstract]
Indefinite-lived Intangible Assets (Excluding Goodwill)	$ 814.0	$ 1,056.9
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Indefinite-lived intangible asset, Percent of Fair Value in Excess of Carrying Amount	13.00%	9.00%

Finite-Lived and Indefinite-Live Intangible Assets [Line Items] [Line Items]

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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