Additional financial information - Other current assets (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Prepayments	$ 396	$ 303	$ 323
Income tax recoverable	147	216	164
Other	41	230	207
Total other current assets	$ 584	$ 749	$ 694

Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

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-Topic 210
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- References

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- Definition

Amount of current assets classified as other.

+ References

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Amount of other miscellaneous assets expected to be realized or consumed within one year or operating cycle, if longer.

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- Definition

Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
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