Retirement benefit obligations - Schedule of Retirement Benefits Recognised in Balance Sheet (Details) - GBP (£) £ in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Disclosure of employee benefits [Abstract] | ||
| Retirement benefit assets | £ 2,695 | £ 3,028 |
| Retirement benefit obligations | (120) | (122) |
| Total amounts recognised in the balance sheet | £ 2,575 | £ 2,906 |
| X | ||||||||||
- Definition The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition The amount of surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| X | ||||||||||
- Definition The amount of deficit in a defined benefit plan. [Refer: Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| X | ||||||||||
- References No definition available.
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