Cash and cash equivalents (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accounting Standards, Amendments and Interpretations Issued but not yet Applied [Abstract]
Cash	$ 389	$ 513
Cash equivalents	252	387
Cash and cash equivalents	$ 641	$ 900	$ 1,162

The amount of cash on hand and demand deposits. [Refer: Cash on hand]

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

The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

+ 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

A classification of cash equivalents representing short-term investments. [Refer: Cash equivalents]

+ References

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Accounting Standards, Amendments and Interpretations Issued but not yet Applied [Abstract]

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No definition available.

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