Statement Of Changes In Equity [Abstract]
| Concept |
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 |
As at 2021-12-31 |
As at 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 |
2020-01-01 to 2020-12-31 |
As at 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 |
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 |
As at 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | |||||||||||||||||||||||||||||||||
| Equity |
3,372,000
GBP
|
1,094,833,000
GBP
|
1,098,205,000
GBP
|
— | — |
2,390,581,000
GBP
|
— |
823,513,000
GBP
|
361,081,000
GBP
|
— |
111,154,000
GBP
|
— | — | — |
899,785,000
GBP
|
— |
111,127,000
GBP
|
— | — |
823,513,000
GBP
|
6,956,000
GBP
|
906,7 41
GBP
|
360,657,000
GBP
|
— | — |
2,195,082,000
GBP
|
— |
841,560,000
GBP
|
1,271,966,000
GBP
|
359,857,000
GBP
|
837,940,000
GBP
|
3,620,000
GBP
|
7 4,169
GBP
|
| Changes in equity [abstract] | |||||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||||||||||||||
| Profit (loss) | — | — | — | — |
254,125,000
GBP
|
— | — | — | — | — | — |
254,125,000
GBP
|
254,125,000
GBP
|
76,813,000
GBP
|
— | — | — | — |
76,813,000
GBP
|
— | — | — | — |
76,813,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Other comprehensive income | — | — | — | — |
24,690,000
GBP
|
— | — | — | — | — | — |
24,690,000
GBP
|
24,690,000
GBP
|
9,530,000
GBP
|
— | — | — | — |
9,530,000
GBP
|
— | — | — | — |
9,530,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Issue of equity | — | — | — | — | — | — |
424,000
GBP
|
— | — |
27,000
GBP
|
— |
451,000
GBP
|
— |
870,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
70,000
GBP
|
— |
800,000
GBP
|
— | — | — | — | — | — |
| Increase through other contributions by owners, equity | — | — | — | — | — | — | — | — | — | — | — | — | — |
855,383,000
GBP
|
— | — | — |
823,513,000
GBP
|
— | — | — | — | — | — |
31,870,000
GBP
|
— | — | — | — | — | — | — | — |
| Increase (decrease) through other changes, equity | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
5,018,000
GBP
|
— | — | — | — |
5,018,000
GBP
|
5,018,000
GBP
|
— | — | — | — | — | — | — | — |
| Increase (decrease) through treasury share transactions, equity | — | — | — | — | — | — | — | — | — | — | — | — | — |
3,500,000
GBP
|
— |
3,500,000
GBP
|
— | — |
3,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Increase (decrease) through share-based payment transactions, equity | — | — | — | — |
4,543,000
GBP
|
— | — | — | — | — | — |
4,543,000
GBP
|
4,543,000
GBP
|
2,741,000
GBP
|
— | — | — | — |
2,7 41
GBP
|
— | — | — | — |
2,7 41
GBP
|
— | — | — | — | — | — | — | — | — |
| Increase (decrease) in equity | — | — | — |
3,584,000
GBP
|
87,351,000
GBP
|
— |
424,000
GBP
|
— | — |
27,000
GBP
|
— |
83,316,000
GBP
|
83,767,000
GBP
|
823,513,000
GBP
|
— |
2,102,000
GBP
|
— |
855,833,000
GBP
|
36,958,000
GBP
|
— | — | — | — |
5,438,000
GBP
|
800,000
GBP
|
— |
3,336,000
GBP
|
— | — | — | — | — | — |