Statement Of Financial Position [Abstract]
| Concept |
As at 2023-12-31 |
As at 2023-12-31 |
As at 2023-12-31 |
As at 2023-12-31 |
As at 2023-12-31 |
As at 2023-12-31 |
As at 2023-12-31 |
As at 2023-12-31 |
As at 2023-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | |||||||||||||||||||||||||||
| Assets [abstract] | |||||||||||||||||||||||||||
| Property, plant and equipment |
504,900,000
GBP
|
— | — | — | — | — | — | — | — |
516 . 3
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Right-of-use assets |
58,500,000
GBP
|
— | — | — | — | — | — | — | — |
59,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Goodwill |
22 1 .5
GBP
|
— | — | — | — | — | — | — | — |
227 .8
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Current tax assets |
13. 1
GBP
|
— | — | — | — | — | — | — | — |
24 .4
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Deferred tax assets |
2,600,000
GBP
|
— | — | — | — | — | — | — | — |
1. 5
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Cash and cash equivalents |
44. 7
GBP
|
— | — | — | — | — | — | — | — |
36,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
37 .9
GBP
|
— | — | — | — | — |
| Assets |
1, 13 6 .7
GBP
|
— | — | — | — | — | — | — | — |
1,16 7.7
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | |||||||||||||||||||||||||||
| Equity [abstract] | |||||||||||||||||||||||||||
| Issued capital |
33. 1
GBP
|
— | — | — | — | — | — | — | — |
33. 1
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Retained earnings |
404. 0
GBP
|
— | — | — | — | — | — | — | — |
359,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Share premium |
177,100,000
GBP
|
— | — | — | — | — | — | — | — |
177,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Treasury shares |
15,600,000
GBP
|
— | — | — | — | — | — | — | — |
5,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Other reserves |
13 9. 9
GBP
|
— | — | — | — | — | — | — | — |
13 4 . 9
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity attributable to owners of parent |
790,800,000
GBP
|
— | — | — | — | — | — | — | — |
780,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Non-controlling interests |
1,500,000
GBP
|
— | — | — | — | — | — | — | — |
1,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity |
792,300,000
GBP
|
40 4 .0
GBP
|
139. 9
GBP
|
1,500,000
GBP
|
177 . 1
GBP
|
33,100,000
GBP
|
5 2. 3
GBP
|
15,600,000
GBP
|
7 90 .8
GBP
|
782,000,000
GBP
|
134,900,000
GBP
|
1. 1
GBP
|
1 77 . 1
GBP
|
35 9.8
GBP
|
5. 2
GBP
|
33,100,000
GBP
|
81,200,000
GBP
|
780 .9
GBP
|
6. 2
GBP
|
319,400,000
GBP
|
137 .5
GBP
|
6 8 5 .4
GBP
|
6 8 4 .7
GBP
|
700,000
GBP
|
1 77 . 1
GBP
|
23 .8
GBP
|
33,100,000
GBP
|
| Liabilities [abstract] | |||||||||||||||||||||||||||
| Current tax liabilities |
46. 0
GBP
|
— | — | — | — | — | — | — | — |
42. 8
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Deferred tax liabilities |
51. 8
GBP
|
— | — | — | — | — | — | — | — |
51,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Liabilities |
344,400,000
GBP
|
— | — | — | — | — | — | — | — |
385. 7
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |