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v3.25.3

Employee benefits - Weighted average duration of benefit obligations (Details) | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024
U.K. |  |
Disclosure of defined benefit plans [line items] |  |
Weighted average duration of defined benefit obligation | 12 years | 13 years
France |  |
Disclosure of defined benefit plans [line items] |  |
Weighted average duration of defined benefit obligation | 16 years | 17 years
GERMANY |  |
Disclosure of defined benefit plans [line items] |  |
Weighted average duration of defined benefit obligation | 9 years | 10 years
Other |  |
Disclosure of defined benefit plans [line items] |  |
Weighted average duration of defined benefit obligation | 9 years | 9 years

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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + References No definition available. + Details
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- Definition The weighted average duration of a defined benefit obligation. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2025-01-01 -Paragraph 147 -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2025-en-r&anchor=para_147_c&doctype=Standard -URIDate 2025-03-27 + Details
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- Details
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- Details
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- Details
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