Statement Of Financial Position [Abstract]
| Concept |
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 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | ||||||||||||||||||
| Assets [abstract] | ||||||||||||||||||
| Property, plant and equipment |
118 .6
GBP
|
— | — | — | — | — |
99,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Investments accounted for using equity method |
300,000
GBP
|
— | — | — | — | — |
300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Current tax assets |
21,800,000
GBP
|
— | — | — | — | — |
21 .4
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Deferred tax assets |
1 0.5
GBP
|
— | — | — | — | — |
9 .7
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Cash and cash equivalents |
8 61 .6
GBP
|
— | — | — | — | — |
1 , 24 6 . 6
GBP
|
— | — | — | — | — |
1 , 2 3 4.1
GBP
|
— | — | — | — | — |
| Assets |
5 , 0 3 4 .1
GBP
|
— | — | — | — | — |
4,792. 2
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | ||||||||||||||||||
| Equity [abstract] | ||||||||||||||||||
| Issued capital |
31,900,000
GBP
|
— | — | — | — | — |
3 1.9
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Retained earnings |
2,868,500,000
GBP
|
— | — | — | — | — |
3 ,0 55 .1
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Share premium |
25,600,000
GBP
|
— | — | — | — | — |
24 . 9
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Equity |
3,439,300,000
GBP
|
25 .6
GBP
|
236,500,000
GBP
|
2,868,500,000
GBP
|
31 .9
GBP
|
276 . 8
GBP
|
3 ,6 25 . 2
GBP
|
3 , 0 55 .1
GBP
|
236,500,000
GBP
|
276. 8
GBP
|
24 . 9
GBP
|
3 1.9
GBP
|
3, 51 8 .4
GBP
|
2,950. 9
GBP
|
3 1.9
GBP
|
236,500,000
GBP
|
22. 3
GBP
|
276 . 8
GBP
|
| Liabilities [abstract] | ||||||||||||||||||
| Deferred tax liabilities |
7 2 .1
GBP
|
— | — | — | — | — |
5 4.6
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Liabilities |
1,594,800,000
GBP
|
— | — | — | — | — |
1 , 1 67. 0
GBP
|
— | — | — | — | — | — | — | — | — | — | — |