Post-employment benefits for associates - Schedule of expected future cash flows (Details) $ in Millions	12 Months Ended
Dec. 31, 2024 USD ($)
Pension plans
Employer contributions
2025 (estimated)	$ 10
Pension plans \| 2025
Expected future benefit payments
Settlements	38
Pension plans \| 2026
Expected future benefit payments
Settlements	34
Pension plans \| 2027
Expected future benefit payments
Settlements	35
Pension plans \| 2028
Expected future benefit payments
Settlements	35
Pension plans \| 2029
Expected future benefit payments
Settlements	38
Pension plans \| 2030-2034
Expected future benefit payments
Settlements	200
Other post-employment benefit plans
Employer contributions
2025 (estimated)	0
Other post-employment benefit plans \| 2025
Expected future benefit payments
Settlements	16
Other post-employment benefit plans \| 2026
Expected future benefit payments
Settlements	18
Other post-employment benefit plans \| 2027
Expected future benefit payments
Settlements	19
Other post-employment benefit plans \| 2028
Expected future benefit payments
Settlements	20
Other post-employment benefit plans \| 2029
Expected future benefit payments
Settlements	20
Other post-employment benefit plans \| 2030-2034
Expected future benefit payments
Settlements	$ 93

Defined Benefit Plan, Expected Future Benefit Payment1 [Abstract]

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- Definition

Defined Benefit Plan, Expected Future Employer Contributions1 [Abstract]

+ References

No definition available.

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- Definition

The estimate of the expected contributions to be made to a defined benefit plan for the next annual reporting period. [Refer: Defined benefit plans [domain]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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- Definition

The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan in respect of settlements. [Refer: Decrease (increase) in net defined benefit liability (asset) resulting from gains (losses) arising from settlements; Net defined benefit liability (asset); Defined benefit plans [domain]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Number 19
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-URIDate 2024-03-27

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