Disposal of assets and other transactions (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Assets classified as held for sale
Property, plant and equipment	$ 521	$ 510
Total	521	510
Liabilities on assets classified as held for sale
Provision for decommissioning costs	722	713
Total	722	$ 713
Exploration And Production Segment [Member]
Assets classified as held for sale
Property, plant and equipment	521
Total	521
Liabilities on assets classified as held for sale
Provision for decommissioning costs	722
Total	$ 722

The amount of liabilities included in disposal groups classified as held for sale. [Refer: Liabilities; Disposal groups classified as held for sale [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URIDate 2024-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
-Paragraph 54
-Subparagraph p
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_54_p&doctype=Standard
-URIDate 2024-03-27

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