Statement Of Changes In Equity [Abstract]
| Concept |
2023-01-01 to 2023-12-31 |
As at 2023-12-31 |
As at 2023-12-31 |
2023-01-01 to 2023-12-31 |
2023-01-01 to 2023-12-31 |
As at 2023-12-31 |
2023-01-01 to 2023-12-31 |
As at 2023-12-31 |
As at 2023-12-31 |
2023-01-01 to 2023-12-31 |
As at 2022-12-31 |
2022-01-01 to 2022-12-31 |
2022-01-01 to 2022-12-31 |
2022-01-01 to 2022-12-31 |
2022-01-01 to 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
2022-01-01 to 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||||||||||||||||||||
| Statement of changes in equity [line items] | |||||||||||||||||||||||||
| Equity | — |
734. 2
GBP
|
303. 8
GBP
|
— | — |
0. 3
GBP
|
— |
6,000,000
GBP
|
42 4 .1
GBP
|
— |
70 0.8
GBP
|
— | — | — | — |
0. 3
GBP
|
249. 8
GBP
|
6,000,000
GBP
|
— |
444. 7
GBP
|
4 59.9
GBP
|
181,400,000
GBP
|
6 4 7. 6
GBP
|
0. 3
GBP
|
6,000,000
GBP
|
| Changes in equity [abstract] | |||||||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||||||
| Profit (loss) |
53,400,000
GBP
|
— | — |
53,400,000
GBP
|
–
GBP
|
— |
–
GBP
|
— | — |
–
GBP
|
— |
–
GBP
|
6 7. 7
GBP
|
6 7. 7
GBP
|
–
GBP
|
— | — | — |
–
GBP
|
— | — | — | — | — | — |
| Comprehensive income |
53,400,000
GBP
|
— | — |
53,400,000
GBP
|
–
GBP
|
— |
–
GBP
|
— | — |
–
GBP
|
— |
–
GBP
|
6 7. 7
GBP
|
6 7. 7
GBP
|
–
GBP
|
— | — | — |
–
GBP
|
— | — | — | — | — | — |
| Dividends recognised as distributions to owners |
2 0.7
GBP
|
— | — |
–
GBP
|
–
GBP
|
— |
–
GBP
|
— | — |
2 0 .7
GBP
|
— |
–
GBP
|
15 . 2
GBP
|
–
GBP
|
15 . 2
GBP
|
— | — | — |
–
GBP
|
— | — | — | — | — | — |
| Increase (decrease) through share-based payment transactions, equity |
700,000
GBP
|
— | — |
700,000
GBP
|
–
GBP
|
— |
–
GBP
|
— | — |
–
GBP
|
— |
–
GBP
|
700,000
GBP
|
0 .7
GBP
|
–
GBP
|
— | — | — |
–
GBP
|
— | — | — | — | — | — |