Risk management - Non derivative hedging instrument (Details) - Cash flow hedging - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Risk management
Opening balance	$ 6,265	$ 5,572
Reassignment of hedging instruments	1,200	970
Realization of exports	(1,207)	(970)
Designation of new coverage	1,085	693
Closing balance	$ 7,343	$ 6,265

The amount of a hedging instrument, recognised as an asset. [Refer: Hedging instruments [domain]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 24A
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_24A_a&doctype=Standard
-URIDate 2024-03-27

Name:	ifrs-full_HedgingInstrumentAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant