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 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 |
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 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2019-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | |||||||||||||||||||||||||||||||
| Assets [abstract] | |||||||||||||||||||||||||||||||
| Property, plant and equipment |
369,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
355,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Right-of-use assets |
74,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
76,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Current tax assets |
1,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
1,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Deferred tax assets |
133,700,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
156,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Cash and cash equivalents |
583,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
418,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — |
418,900,000
GBP
|
— | — |
489,400,000
GBP
|
| Assets |
3,104,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
2,842,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | |||||||||||||||||||||||||||||||
| Equity [abstract] | |||||||||||||||||||||||||||||||
| Issued capital |
69,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
11,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Retained earnings |
1,184,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
662,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Share premium |
1,697,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
1,123,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity attributable to owners of parent |
753,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
641,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Non-controlling interests |
19,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
18,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity |
772,500,000
GBP
|
19,500,000
GBP
|
1,697,400,000
GBP
|
9,300,000
GBP
|
1,184,900,000
GBP
|
69,900,000
GBP
|
6,500,000
GBP
|
143,900,000
GBP
|
4,300,000
GBP
|
6,600,000
GBP
|
6,600,000
GBP
|
662,400,000
GBP
|
9,300,000
GBP
|
660,400,000
GBP
|
6,700,000
GBP
|
143,900,000
GBP
|
18,600,000
GBP
|
1,123,400,000
GBP
|
2,700,000
GBP
|
11,600,000
GBP
|
503,100,000
GBP
|
16,300,000
GBP
|
10,900,000
GBP
|
11,500,000
GBP
|
144,000,000
GBP
|
400,000
GBP
|
1,108,200,000
GBP
|
804,100,000
GBP
|
6,600,000
GBP
|
9,300,000
GBP
|
— |
| Liabilities [abstract] | |||||||||||||||||||||||||||||||
| Current tax liabilities |
6,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
5,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Deferred tax liabilities |
700,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Liabilities |
2,331,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — |
2,182,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |