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 |
As at 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 |
2022-01-01 to 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 |
2021-01-01 to 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 |
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 |
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 |
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 |
As at 2020-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||||||||||||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | |||||||||||||||||||||||||||||||||||||||||||||
| Equity |
1, 5 4 8
GBP
|
— | — | — | — | — |
1,000,000
GBP
|
— |
58,000,000
GBP
|
346,000,000
GBP
|
41,000,000
GBP
|
989,000,000
GBP
|
11 5
GBP
|
–
GBP
|
— |
–
GBP
|
— | — | — |
1, 4 8 2
GBP
|
17,000,000
GBP
|
— |
1,000,000
GBP
|
— |
1,7 3 9
GBP
|
— | — | — |
–
GBP
|
25,000,000
GBP
|
58,000,000
GBP
|
— |
42,000,000
GBP
|
116,000,000
GBP
|
— | — |
–
GBP
|
1, 49 5
GBP
|
12 5
GBP
|
149,000,000
GBP
|
1,000,000
GBP
|
42,000,000
GBP
|
58,000,000
GBP
|
1,87 8
GBP
|
8,000,000
GBP
|
| Changes in equity [abstract] | |||||||||||||||||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||||||||||||||||||||||||||
| Profit (loss) | — |
–
GBP
|
–
GBP
|
17 5
GBP
|
17 5
GBP
|
–
GBP
|
— |
–
GBP
|
— | — | — | — | — | — |
–
GBP
|
— |
–
GBP
|
–
GBP
|
–
GBP
|
— | — |
–
GBP
|
— |
–
GBP
|
— |
–
GBP
|
–
GBP
|
–
GBP
|
— | — | — |
–
GBP
|
— | — |
15 4
GBP
|
15 4
GBP
|
— | — | — | — | — | — | — | — | — |
| Other comprehensive income | — | — | — |
–
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
–
GBP
|
— | — |
–
GBP
|
— |
1,000,000
GBP
|
— |
–
GBP
|
–
GBP
|
–
GBP
|
— | — | — |
–
GBP
|
— | — |
1,000,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — |
| Comprehensive income | — |
–
GBP
|
–
GBP
|
17 5
GBP
|
17 5
GBP
|
–
GBP
|
— |
–
GBP
|
— | — | — | — | — | — |
–
GBP
|
— |
–
GBP
|
–
GBP
|
–
GBP
|
— | — |
–
GBP
|
— |
1,000,000
GBP
|
— |
–
GBP
|
–
GBP
|
–
GBP
|
— | — | — |
–
GBP
|
— | — |
153,000,000
GBP
|
15 4
GBP
|
— | — | — | — | — | — | — | — | — |
| Issue of equity | — |
–
GBP
|
–
GBP
|
–
GBP
|
3 03
GBP
|
–
GBP
|
— |
25,000,000
GBP
|
— | — | — | — | — | — |
328,000,000
GBP
|
— |
–
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Dividends recognised as distributions to owners | — |
–
GBP
|
–
GBP
|
78,000,000
GBP
|
78,000,000
GBP
|
–
GBP
|
— |
–
GBP
|
— | — | — | — | — | — |
–
GBP
|
— |
–
GBP
|
–
GBP
|
–
GBP
|
— | — |
–
GBP
|
— |
–
GBP
|
— |
–
GBP
|
–
GBP
|
–
GBP
|
— | — | — |
–
GBP
|
— | — |
89,000,000
GBP
|
8 9
GBP
|
— | — | — | — | — | — | — | — | — |
| Increase (decrease) through treasury share transactions, equity | — |
–
GBP
|
–
GBP
|
22,000,000
GBP
|
22,000,000
GBP
|
–
GBP
|
— |
–
GBP
|
— | — | — | — | — | — |
–
GBP
|
— |
–
GBP
|
–
GBP
|
–
GBP
|
— | — |
–
GBP
|
— |
–
GBP
|
— |
–
GBP
|
–
GBP
|
–
GBP
|
— | — | — |
–
GBP
|
— | — |
20,000,000
GBP
|
20,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Increase (decrease) through share-based payment transactions, equity | — |
–
GBP
|
–
GBP
|
24,000,000
GBP
|
23,000,000
GBP
|
–
GBP
|
— |
–
GBP
|
— | — | — | — | — | — |
–
GBP
|
— |
1,000,000
GBP
|
–
GBP
|
–
GBP
|
— | — |
–
GBP
|
— |
–
GBP
|
— |
–
GBP
|
1,000,000
GBP
|
–
GBP
|
— | — | — |
–
GBP
|
— | — |
20,000,000
GBP
|
21,000,000
GBP
|
— | — | — | — | — | — | — | — | — |