Financial Liabilities - Borrowings - Summary of Maturities of the Group's Non-Current Borrowings (Detail) - GBP (£) £ in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Disclosure of detailed information about borrowings [line items] | ||
| Non-current borrowings | £ 1,419 | £ 1,157 |
| Later than one year and not later than two years [member] | ||
| Disclosure of detailed information about borrowings [line items] | ||
| Non-current borrowings | 70 | 71 |
| Between two and five years [member] | ||
| Disclosure of detailed information about borrowings [line items] | ||
| Non-current borrowings | 778 | 149 |
| Later than five years [member] | ||
| Disclosure of detailed information about borrowings [line items] | ||
| Non-current borrowings | £ 571 | £ 937 |