Statement Of Changes In Equity [Abstract]
| Concept |
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 |
2023-01-01 to 2023-12-31 |
As at 2023-12-31 |
2023-01-01 to 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 |
2023-01-01 to 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 |
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 |
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 |
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 |
2022-01-01 to 2022-12-31 |
2022-01-01 to 2022-12-31 |
2022-01-01 to 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 changes in equity [abstract] | |||||||||||||||||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | |||||||||||||||||||||||||||||||||||||||||||||
| 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
|
1 77 . 1
GBP
|
23 .8
GBP
|
33,100,000
GBP
|
700,000
GBP
|
| Changes in equity [abstract] | |||||||||||||||||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||||||||||||||||||||||||||
| Profit (loss) |
–
GBP
|
86,800,000
GBP
|
— |
8 5.6
GBP
|
–
GBP
|
— |
1,200,000
GBP
|
— |
8 5.6
GBP
|
–
GBP
|
— |
–
GBP
|
— |
–
GBP
|
— | — | — | — | — |
–
GBP
|
–
GBP
|
–
GBP
|
74 . 3
GBP
|
7 3.7
GBP
|
0. 6
GBP
|
— | — | — | — | — | — | — | — |
73 .7
GBP
|
–
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — |
| Other comprehensive income | — |
27,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
59. 4
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Comprehensive income |
–
GBP
|
58,900,000
GBP
|
— |
58 .5
GBP
|
1,900,000
GBP
|
— |
400,000
GBP
|
— |
85 .5
GBP
|
–
GBP
|
— |
28 .9
GBP
|
— |
–
GBP
|
— | — | — | — | — |
–
GBP
|
–
GBP
|
3. 4
GBP
|
13 3 . 7
GBP
|
79. 3
GBP
|
0. 4
GBP
|
— | — | — | — | — | — | — | — |
13 3. 3
GBP
|
–
GBP
|
57 .4
GBP
|
— | — | — | — | — | — | — | — | — |
| Dividends recognised as distributions to owners |
–
GBP
|
40. 6
GBP
|
— |
40,600,000
GBP
|
–
GBP
|
— |
–
GBP
|
— |
4 0.6
GBP
|
–
GBP
|
— |
–
GBP
|
— |
–
GBP
|
— | — | — | — | — |
–
GBP
|
–
GBP
|
–
GBP
|
3 8 .5
GBP
|
3 8 .5
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — |
3 8 .5
GBP
|
–
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — |
| Increase (decrease) through share-based payment transactions, equity |
–
GBP
|
5. 1
GBP
|
— |
5,100,000
GBP
|
5. 1
GBP
|
— |
–
GBP
|
— |
–
GBP
|
–
GBP
|
— |
–
GBP
|
— |
–
GBP
|
— | — | — | — | — |
–
GBP
|
–
GBP
|
1 .7
GBP
|
1 .7
GBP
|
–
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — |
1 .7
GBP
|
–
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — |