Statement Of Changes In Equity [Abstract]
| Concept |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
2019-01-01 to 2019-12-31 |
2019-01-01 to 2019-12-31 |
2019-01-01 to 2019-12-31 |
2019-01-01 to 2019-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||||||
| Statement of changes in equity [line items] | |||||||||||
| Dividends recognised as distributions to owners of parent |
1,358,000,000
GBP
|
1,358,000,000
GBP
|
1,358,000,000
GBP
|
129,000,000
GBP
|
129,000,000
GBP
|
— |
129,000,000
GBP
|
315,000,000
GBP
|
315,000,000
GBP
|
315,000,000
GBP
|
— |
| Dividends recognised as distributions to non-controlling interests | — |
—
GBP
|
— | — |
15,000,000
GBP
|
15,000,000
GBP
|
— | — | — |
12,000,000
GBP
|
12,000,000
GBP
|