Statement Of Changes In Equity [Abstract]
| Concept |
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 |
|---|---|---|---|---|
| Statement of changes in equity [abstract] | ||||
| Statement of changes in equity [line items] | ||||
| Dividends recognised as distributions to non-controlling interests | — | — |
15,000,000
GBP
|
15,000,000
GBP
|
| Increase (decrease) through disposal of subsidiary, equity |
181,000,000
GBP
|
181,000,000
GBP
|
— | — |