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Provisions - Schedule of main categories of plan assets, United Kingdom (Details) - United Kingdom | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Equity instruments |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Plan assets as a percentage of total plan assets | 0.00% | 0.00% | 0.00%
Debt instruments |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Plan assets as a percentage of total plan assets | 67.00% | 66.00% | 62.00%
Properties |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Plan assets as a percentage of total plan assets | 11.00% | 14.00% | 12.00%
Other |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Plan assets as a percentage of total plan assets | 22.00% | 20.00% | 26.00%

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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. + References No definition available. + Details
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