Goodwill (Schedule of Accumulated Impairment Losses) (Details) - USD ($) $ in Millions	Jun. 30, 2025	Sep. 30, 2024
Goodwill [Line Items]
Goodwill, gross	$ 1,253.8	$ 1,199.8
Goodwill, net	969.7	905.1
Americas
Goodwill [Line Items]
Goodwill, accumulated impairment losses	(284.1)	(294.7)
Goodwill, net	$ 144.8	$ 146.3

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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+ Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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