Analysis Of Income And Expense [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 |
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 |
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 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Analysis of income and expense [abstract] | |||||||||||||||||
| Revenue [abstract] | |||||||||||||||||
| Revenue | — |
–
GBP
|
— |
443,300,000
GBP
|
— | — |
443,300,000
GBP
|
— | — | — |
–
GBP
|
358,200,000
GBP
|
— | — |
–
GBP
|
358,200,000
GBP
|
— |
| Material income and expense [abstract] | |||||||||||||||||
| Other finance income | — |
–
GBP
|
— |
0 .1
GBP
|
— | — |
0 .1
GBP
|
— | — | — |
–
GBP
|
200,000
GBP
|
— | — |
–
GBP
|
200,000
GBP
|
— |
| Comprehensive income, continuing and discontinued operations [abstract] | |||||||||||||||||
| Comprehensive income |
4,300,000
GBP
|
— |
2. 7
GBP
|
— |
–
GBP
|
52,900,000
GBP
|
5 7. 2
GBP
|
55,600,000
GBP
|
30,000,000
GBP
|
–
GBP
|
— |
26,700,000
GBP
|
3 .1
GBP
|
29,800,000
GBP
|
— | — |
0. 2
GBP
|
| Comprehensive income attributable to owners of parent, continuing and discontinued operations [abstract] | |||||||||||||||||
| Comprehensive income, attributable to owners of parent | — | — | — | — | — | — |
52,900,000
GBP
|
— | — | — | — |
29,800,000
GBP
|
— | — | — | — | — |
| Comprehensive income attributable to non-controlling interests, continuing and discontinued operations [abstract] | |||||||||||||||||
| Comprehensive income, attributable to non-controlling interests | — | — | — | — | — | — |
4,300,000
GBP
|
— | — | — | — |
3 .1
GBP
|
— | — | — | — | — |