Capital commitments and contingent liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Capital commitments and contingent liabilities.
Commitments to purchase property, plant and equipment	$ 98.6	$ 96.9

The amount of contractual commitments for the acquisition of property, plant and equipment. [Refer: Property, plant and equipment]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 16
-IssueDate 2025-01-01
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-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
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-IssueDate 2025-01-01
-Paragraph 201
-Subparagraph b
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-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 201
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-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_201_b&doctype=Standard
-URIDate 2025-03-27

Name:	ifrs-full_ContractualCommitmentsForAcquisitionOfPropertyPlantAndEquipment
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant