Statement Of Changes In Equity [Abstract]
| Concept |
2021-01-01 to 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
As at 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
2021-01-01 to 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Equity | — |
1, 0 0 8 . 7
GBP
|
142 .1
GBP
|
2 2 7. 1
GBP
|
— | — |
1,13 0 . 5
GBP
|
— | — | — | — |
1,10 8 . 9
GBP
|
14 6 . 7
GBP
|
— |
2 1. 6
GBP
|
38,500,000
GBP
|
— | — |
962 .8
GBP
|
— |
19 . 3
GBP
|
1, 0 41. 9
GBP
|
3 9. 4
GBP
|
— | — | — |
24 8. 2
GBP
|
14 6 . 7
GBP
|
— | — |
1 , 0 61. 2
GBP
|
— | — |
141. 2
GBP
|
— | — |
1, 2 9 8 . 6
GBP
|
40,000,000
GBP
|
1, 2 7 8 . 3
GBP
|
20,300,000
GBP
|
19 0 . 4
GBP
|
20,300,000
GBP
|
1, 2 7 7. 7
GBP
|
14 6 . 7
GBP
|
1 ,1 2 0 . 5
GBP
|
19 0 . 4
GBP
|
14 6 . 7
GBP
|
14 0 . 6
GBP
|
2 0 .9
GBP
|
40,000,000
GBP
|
2 0.9
GBP
|
–
GBP
|
2 0 .9
GBP
|
–
GBP
|
–
GBP
|
14 0 . 6
GBP
|
–
GBP
|
–
GBP
|
1 , 2 5 7. 4
GBP
|
1,1 41 . 4
GBP
|
| Changes in equity [abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Profit (loss) |
4 .9
GBP
|
— | — | — |
–
GBP
|
117 . 0
GBP
|
— |
–
GBP
|
224,400,000
GBP
|
10 2 . 5
GBP
|
–
GBP
|
— | — |
–
GBP
|
— | — |
121. 9
GBP
|
11 7. 0
GBP
|
— |
1 3 9 .1
GBP
|
— | — | — |
1 42.0
GBP
|
93,800,000
GBP
|
2 3 2 .9
GBP
|
— | — |
–
GBP
|
–
GBP
|
— |
2 .9
GBP
|
–
GBP
|
— |
1 42.0
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Other comprehensive income |
0. 8
GBP
|
— | — | — |
22 .0
GBP
|
7 9. 8
GBP
|
— |
–
GBP
|
— | — |
–
GBP
|
— | — |
–
GBP
|
— | — |
7 9. 0
GBP
|
5 7. 8
GBP
|
— |
4 6 .9
GBP
|
— | — | — |
12. 0
GBP
|
— | — | — | — |
59,300,000
GBP
|
–
GBP
|
— |
400,000
GBP
|
–
GBP
|
— |
4 7. 3
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Comprehensive income |
4 .1
GBP
|
— | — | — |
22,000,000
GBP
|
19 6 . 8
GBP
|
— |
–
GBP
|
— | — |
–
GBP
|
— | — |
–
GBP
|
— | — |
2 0 0 .9
GBP
|
174 . 8
GBP
|
— |
18 6 . 0
GBP
|
— | — | — |
13 0 . 0
GBP
|
— | — | — | — |
59,300,000
GBP
|
–
GBP
|
— |
3,300,000
GBP
|
–
GBP
|
— |
18 9. 3
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Dividends recognised as distributions to owners | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
–
GBP
|
— | — | — |
–
GBP
|
— | — | — | — |
–
GBP
|
–
GBP
|
— |
–
GBP
|
–
GBP
|
— |
–
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Increase (decrease) through share-based payment transactions, equity |
–
GBP
|
— | — | — |
–
GBP
|
10 . 0
GBP
|
— |
–
GBP
|
— | — |
–
GBP
|
— | — |
–
GBP
|
— | — |
10 . 0
GBP
|
10 . 0
GBP
|
— |
3,700,000
GBP
|
— | — | — |
3,700,000
GBP
|
— | — | — | — |
–
GBP
|
–
GBP
|
— |
–
GBP
|
–
GBP
|
— |
3,700,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |