Post-employment benefits for associates - Schedule of expected future cash flows (Details) $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($)
Pension plans
Employer contributions
2023 (estimated)	$ 11
Other post-employment benefit plans
Employer contributions
2023 (estimated)	0
2023 \| Pension plans
Expected future benefit payments
Settlements	36
2023 \| Other post-employment benefit plans
Expected future benefit payments
Settlements	16
2024 \| Pension plans
Expected future benefit payments
Settlements	43
2024 \| Other post-employment benefit plans
Expected future benefit payments
Settlements	18
2025 \| Pension plans
Expected future benefit payments
Settlements	40
2025 \| Other post-employment benefit plans
Expected future benefit payments
Settlements	19
2026 \| Pension plans
Expected future benefit payments
Settlements	34
2026 \| Other post-employment benefit plans
Expected future benefit payments
Settlements	20
2027 \| Pension plans
Expected future benefit payments
Settlements	32
2027 \| Other post-employment benefit plans
Expected future benefit payments
Settlements	20
2028-2032 \| Pension plans
Expected future benefit payments
Settlements	193
2028-2032 \| Other post-employment benefit plans
Expected future benefit payments
Settlements	$ 97

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 [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2022-03-24
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2022-03-24
-Paragraph 148
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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 [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
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-URIDate 2022-03-24

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