Contingencies and commitments - Summary of indemnities and other performance guarantees (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Contingencies And Commitments [Abstract]
Contingent liabilities, indemnities and other performance guarantees	$ 322	$ 192
Contingent liabilities incurred in relation to interests in joint ventures and associates	$ 0	$ 0

The amount of the estimated financial effect of contingent liabilities. [Refer: Classes of contingent liabilities [domain]]

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
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