Retirement benefit obligations - Schedule of Movement in Retirement Benefit Net Amounts Recognized in Balance Sheet (Details) - GBP (£) £ in Millions |
12 Months Ended | |
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Dec. 31, 2025 |
Dec. 31, 2024 |
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| RETIREMENT BENEFIT OBLIGATIONS (Details) - Schedule of Movements in Oher Post-Retirement Benefits Obligation [Line Items] | ||
| At 1 January | £ 2,906 | |
| At 31 December | 2,575 | £ 2,906 |
| Defined benefit pension schemes | ||
| RETIREMENT BENEFIT OBLIGATIONS (Details) - Schedule of Movements in Oher Post-Retirement Benefits Obligation [Line Items] | ||
| At 1 January | 2,945 | 3,532 |
| Net defined benefit pension credit | 39 | 13 |
| Actuarial gains on defined benefit obligation | 412 | 2,940 |
| Return on plan assets | (934) | (3,712) |
| Employer contributions | 150 | 172 |
| At 31 December | £ 2,612 | £ 2,945 |
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- Definition The decrease (increase) in net defined benefit liability (asset) resulting from contributions to a defined benefit plan by the employer. [Refer: Net defined benefit liability (asset); Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from the remeasurement of that net defined benefit liability (asset). [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- 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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- Definition RETIREMENT BENEFIT OBLIGATIONS (Details) - Schedule of Movements in Oher Post-Retirement Benefits Obligation [Line Items] No definition available.
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- Details
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