Statement Of Changes In Equity [Abstract]
| Concept |
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 |
2022-01-01 to 2022-12-31 |
2022-01-01 to 2022-12-31 |
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 |
2021-01-01 to 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 |
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 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||||||||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | |||||||||||||||||||||||||||||||||||||||||
| Equity |
4 ,1 60 . 4
GBP
|
— | — | — | — | — | — |
285,200,000
GBP
|
4 7 9. 6
GBP
|
575 .9
GBP
|
3,75 9 .7
GBP
|
1 ,0 5 4 .1
GBP
|
1 14 .1
GBP
|
3,6 80.8
GBP
|
— | — | — |
1 ,11 2 .1
GBP
|
4 , 3 67. 3
GBP
|
3 3 5.9
GBP
|
— | — | — |
4 , 0 6 9. 0
GBP
|
— |
3,61 6.4
GBP
|
5 74 . 7
GBP
|
— |
4 52. 6
GBP
|
122. 4
GBP
|
— | — |
570. 3
GBP
|
— |
4 ,9 5 9. 2
GBP
|
3 1 8 .1
GBP
|
1 2 9. 6
GBP
|
4,732. 0
GBP
|
191. 2
GBP
|
1 ,1 1 8 . 3
GBP
|
5, 0 5 0 .1
GBP
|
| Changes in equity [abstract] | |||||||||||||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||||||||||||||||||||||
| Profit (loss) | — |
–
GBP
|
−
GBP
|
–
GBP
|
775 . 4
GBP
|
682 .7
GBP
|
92. 7
GBP
|
— | — | — | — | — | — | — |
682. 7
GBP
|
–
GBP
|
8 3 .0
GBP
|
— | — | — |
−
GBP
|
−
GBP
|
6 3 7. 7
GBP
|
— |
−
GBP
|
— | — |
−
GBP
|
— | — |
720,700,000
GBP
|
6 3 7. 7
GBP
|
— |
2, 901.3
GBP
|
— | — | — | — | — | — | — |
| Other comprehensive income | — |
–
GBP
|
–
GBP
|
2 9 9. 4
GBP
|
320. 8
GBP
|
6,200,000
GBP
|
15. 2
GBP
|
— | — | — | — | — | — | — |
305,600,000
GBP
|
–
GBP
|
10. 3
GBP
|
— | — | — |
−
GBP
|
7 9.9
GBP
|
97 .9
GBP
|
— |
−
GBP
|
— | — |
−
GBP
|
— | — |
10 8. 2
GBP
|
18 .0
GBP
|
— |
115,300,000
GBP
|
— | — | — | — | — | — | — |
| Comprehensive income | — |
–
GBP
|
–
GBP
|
2 9 9. 4
GBP
|
1,096 .2
GBP
|
6 8 8 .9
GBP
|
1 0 7. 9
GBP
|
— | — | — | — | — | — | — |
988 .3
GBP
|
–
GBP
|
72 .7
GBP
|
— | — | — |
−
GBP
|
7 9.9
GBP
|
5 3 9. 8
GBP
|
— |
−
GBP
|
— | — |
−
GBP
|
— | — |
6 12.5
GBP
|
61 9. 7
GBP
|
— |
3,016,600,000
GBP
|
— | — | — | — | — | — | — |
| Issue of equity | — |
−
GBP
|
−
GBP
|
−
GBP
|
1,200,000
GBP
|
−
GBP
|
−
GBP
|
— | — | — | — | — | — | — |
1,200,000
GBP
|
1,200,000
GBP
|
−
GBP
|
— | — | — |
−
GBP
|
−
GBP
|
4 .4
GBP
|
— |
4,400,000
GBP
|
— | — |
−
GBP
|
— | — |
4,400,000
GBP
|
−
GBP
|
— | — | — | — | — | — | — | — | — |
| Dividends recognised as distributions to owners | — |
–
GBP
|
–
GBP
|
–
GBP
|
4 3 4 .9
GBP
|
3 65 . 4
GBP
|
6 9. 5
GBP
|
— | — | — | — | — | — | — |
3 6 5 . 4
GBP
|
–
GBP
|
114 .5
GBP
|
— | — | — |
−
GBP
|
−
GBP
|
314. 7
GBP
|
— |
−
GBP
|
— | — |
−
GBP
|
— | — |
4 2 9. 2
GBP
|
314 .7
GBP
|
— | — | — | — | — | — | — | — | — |
| Increase (decrease) through treasury share transactions, equity | — |
−
GBP
|
−
GBP
|
−
GBP
|
−
GBP
|
−
GBP
|
−
GBP
|
— | — | — | — | — | — | — |
−
GBP
|
−
GBP
|
−
GBP
|
— | — | — |
3,700,000
GBP
|
−
GBP
|
–
GBP
|
— |
−
GBP
|
— | — |
−
GBP
|
— | — |
−
GBP
|
3,700,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Increase (decrease) through share-based payment transactions, equity | — |
–
GBP
|
–
GBP
|
–
GBP
|
122 .0
GBP
|
122 .0
GBP
|
–
GBP
|
— | — | — | — | — | — | — |
12 2.0
GBP
|
–
GBP
|
−
GBP
|
— | — | — |
−
GBP
|
−
GBP
|
9 9. 6
GBP
|
— |
−
GBP
|
— | — |
−
GBP
|
— | — |
9 9. 6
GBP
|
9 9. 6
GBP
|
— | — | — | — | — | — | — | — | — |