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 |
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] | ||||||
| Increase (decrease) through acquisition of subsidiary, equity |
1,300,000
GBP
|
— |
9,600,000
GBP
|
8,300,000
GBP
|
— | — |
| Increase (decrease) through transfer to statutory reserve, equity | — |
10,400,000
GBP
|
— |
10,400,000
GBP
|
— | — |
| Increase (decrease) through transactions with owners, equity | — | — |
7 .8
GBP
|
7 .8
GBP
|
1 .1
GBP
|
1 .1
GBP
|