Asset retirement obligations - Schedule of Asset Retirement Obligations (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Asset Retirement Obligation Disclosure [Abstract] | ||
| Current ARO liability | $ 39 | $ 39 |
| Noncurrent ARO liability | 251 | 255 |
| Total ARO liability | $ 290 | $ 294 |
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- Definition The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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