Deferred tax - Components of deferred income tax assets and liabilities (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Deferred income tax
Deferred tax assets	$ 268	$ 283
Available for offset	(204)	(221)
Net deferred tax assets after offset	64	62
Deferred tax liabilities	(345)	(357)
Available for offset	204	221
Net Deferred tax liabilities After offset	(141)	(136)
Tax losses
Deferred income tax
Deferred tax assets	53	39
Employee benefit obligations
Deferred income tax
Deferred tax assets	19	23
Depreciation timing differences (including leases)
Deferred income tax
Deferred tax assets	123	147
Provisions
Deferred income tax
Deferred tax assets	29	29
Other
Deferred income tax
Deferred tax assets	44	45
Deferred tax liabilities	(14)	(16)
Intangible assets
Deferred income tax
Deferred tax liabilities	(85)	(101)
Accelerated depreciation and other fair value adjustments (including leases)
Deferred income tax
Deferred tax liabilities	$ (246)	$ (240)

The amount of deferred tax asset available for offset against deferred tax liabilities.

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- Definition

The amount of deferred tax (liabilities) available for offset against deferred tax assets.

+ References

No definition available.

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- Definition

The amounts of income taxes recoverable in future periods in respect of: (a) deductible temporary differences; (b) the carryforward of unused tax losses; and (c) the carryforward of unused tax credits. [Refer: Temporary differences [member]; Unused tax credits [member]; Unused tax losses [member]]

+ References

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

The amounts of income taxes payable in future periods in respect of taxable temporary differences. [Refer: Temporary differences [member]]

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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- Definition

The amount of deferred tax assets net of deferred tax liabilities, when the absolute amount of deferred tax assets is greater than the absolute amount of deferred tax liabilities. [Refer: Deferred tax assets; Deferred tax liabilities]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The amount of deferred tax liabilities net of deferred tax assets, when the absolute amount of deferred tax liabilities is greater than the absolute amount of deferred tax assets. [Refer: Deferred tax assets; Deferred tax liabilities]

+ References

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