Financial instruments and Retirement benefit obligations - Financial instruments - Transfers (Details) - USD ($) $ in Millions |
1 Months Ended | 6 Months Ended | 12 Months Ended |
|---|---|---|---|
Jan. 31, 2026 |
Jun. 27, 2026 |
Dec. 31, 2025 |
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| Disclosure of detailed information about financial instruments [line items] | |||
| Transfer from Level 1 to Level 2 assets | $ 0 | $ 0 | |
| Transfer from Level 2 to Level 1 assets | 0 | 0 | |
| Transfer from Level 1 to Level 2 liabilities | 0 | 0 | |
| Transfer from Level 2 to Level 1 liabilities | $ 0 | 0 | |
| Transfer into Level 3 assets | 0 | ||
| Transfer out of Level 3 assets | 0 | ||
| Transfer into Level 3 liabilities | 0 | ||
| Transfer out of Level 3 liabilities | $ 0 | ||
| Investments. | |||
| Disclosure of detailed information about financial instruments [line items] | |||
| Transfer out of Level 3 assets | $ 20 |
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- Definition 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. No definition available.
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- Definition The amount of transfers of assets into Level 3 of the fair value hierarchy. [Refer: Level 3 of fair value hierarchy [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of transfers of liabilities into Level 3 of the fair value hierarchy. [Refer: Level 3 of fair value hierarchy [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of transfers out of Level 1 and into Level 2 of the fair value hierarchy of assets held at the end of the reporting period. [Refer: Level 1 of fair value hierarchy [member]; Level 2 of fair value hierarchy [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of transfers out of Level 1 and into Level 2 of the fair value hierarchy of liabilities held at the end of the reporting period. [Refer: Level 1 of fair value hierarchy [member]; Level 2 of fair value hierarchy [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of transfers out of Level 2 and into Level 1 of the fair value hierarchy of assets held at the end of the reporting period. [Refer: Level 1 of fair value hierarchy [member]; Level 2 of fair value hierarchy [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of transfers out of Level 2 and into Level 1 of the fair value hierarchy of liabilities held at the end of the reporting period. [Refer: Level 1 of fair value hierarchy [member]; Level 2 of fair value hierarchy [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of transfers of assets out of Level 3 of the fair value hierarchy. [Refer: Level 3 of fair value hierarchy [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of transfers of liabilities out of Level 3 of the fair value hierarchy. [Refer: Level 3 of fair value hierarchy [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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