Earnings per share - summary of diluted headline earnings per share (Details) - £ / shares |
6 Months Ended | |
|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
|
| Earnings per share [abstract] | ||
| Earnings per share - diluted (in GBP per share) | £ 2.036 | £ 2.003 |
| Effect of impairment of intangibles property plant and equipment associates and held for sale assets (net of tax) (in GBP per share) | 0.030 | 0.168 |
| Effect of gains on disposal of property, plant and equipment, trademarks, held-for-sale assets, partial/full termination of IFRS 16 leases, and sale and leaseback (net of tax) (in GBP per share) | (0.008) | (0.014) |
| Issue of shares and change in shareholding of an associate (in GBP per share) | (0.001) | (0.003) |
| Gain on partial disposal of an associate and associated capital gains tax (in GBP per share) | (0.380) | (0.586) |
| Diluted headline earnings per share (in GBP per share) | £ 1.677 | £ 1.568 |