Contingencies and commitments (Detail) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Disclosure of contingent liabilities [line items]
Total commitments for capital expenditure	$ 3	$ 8
Joint ventures
Disclosure of contingent liabilities [line items]
Capital and other commitments	$ 5
Associates
Disclosure of contingent liabilities [line items]
Capital and other commitments		$ 16

The amount of future capital expenditures that the entity is committed to make.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
-IssueDate 2025-01-01
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_112_c&doctype=Standard
-URIDate 2025-03-27

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- Definition

The amount of capital commitments for which the entity has entered into a contract. [Refer: Capital commitments]

+ References

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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.

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