Income Tax - Summary of Components of Current Tax Expense Income and Adjustments for Current Tax of Prior Periods (Detail) - GBP (£) £ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
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| Major components of tax expense (income) [abstract] | |||
| Charge in respect of current year | £ (108) | £ (132) | £ (105) |
| Adjustments in respect of prior years | (6) | 60 | 20 |
| Total current tax charge | 114 | 72 | 85 |
| Deferred tax | |||
| In respect of temporary differences | (9) | 8 | (11) |
| Other adjustments in respect of prior years | 2 | (11) | (17) |
| Total deferred tax charge | (7) | (3) | (28) |
| Total tax charge | £ (121) | £ (75) | £ (113) |
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- References Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- References Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The amount of tax expense (income) relating to changes in deferred tax liabilities and deferred tax assets. [Refer: Deferred tax assets; Deferred tax liabilities] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- References Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- References Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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