Goodwill and intangible assets - Narrative (Details) - USD ($) $ in Millions |
6 Months Ended | |
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Mar. 31, 2023 |
Sep. 30, 2022 |
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| Goodwill [Line Items] | ||
| Indefinite-lived intangible assets | $ 763.4 | $ 762.5 |
| Cumulative translation adjustment | $ 16.4 |
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- Definition Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- 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. No definition available.
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- Definition Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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