Statement Of Comprehensive Income [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 |
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 |
2020-01-01 to 2020-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of comprehensive income [abstract] | ||||||||||||||||||||
| Profit (loss) |
0. 5
GBP
|
–
GBP
|
–
GBP
|
7 9.7
GBP
|
–
GBP
|
–
GBP
|
10 5 .1
GBP
|
–
GBP
|
2 5 .9
GBP
|
79. 2
GBP
|
1 5 7. 9
GBP
|
1 5 7. 9
GBP
|
27 5.5
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
1 1 7. 6
GBP
|
–
GBP
|
–
GBP
|
| Other comprehensive income [abstract] | ||||||||||||||||||||
| Components of other comprehensive income that will not be reclassified to profit or loss, before tax [abstract] | ||||||||||||||||||||
| Other comprehensive income, before tax, gains (losses) on remeasurements of defined benefit plans | — | — | — | — | — | — | — | — | — |
30,700,000
GBP
|
1 .4
GBP
|
— | — | — | — | — | — | — | — | — |
| Components of other comprehensive income that will be reclassified to profit or loss, before tax [abstract] | ||||||||||||||||||||
| Cash flow hedges [abstract] | ||||||||||||||||||||
| Gains (losses) on cash flow hedges, before tax | — | — | — | — | — | — | — | — | — |
182 . 0
GBP
|
3 8 . 4
GBP
|
— | — | — | — | — | — | — | — | — |
| Reclassification adjustments on cash flow hedges, before tax | — | — | — | — | — | — | — | — | — |
12 .6
GBP
|
35. 7
GBP
|
— | — | — | — | — | — | — | — | — |
| Cost of hedging [abstract] | ||||||||||||||||||||
| Change in value of foreign currency basis spreads [abstract] | ||||||||||||||||||||
| Other comprehensive income, before tax, change in value of foreign currency basis spreads | — | — | — | — | — | — | — | — | — |
1 7. 3
GBP
|
53,300,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Income tax relating to components of other comprehensive income that will not be reclassified to profit or loss [abstract] | ||||||||||||||||||||
| Income tax relating to remeasurements of defined benefit plans included in other comprehensive income | — | — | — | — | — | — | — | — | — |
7. 2
GBP
|
0. 3
GBP
|
— | — | — | — | — | — | — | — | — |
| Income tax relating to components of other comprehensive income that will be reclassified to profit or loss [abstract] | ||||||||||||||||||||
| Income tax relating to cash flow hedges included in other comprehensive income | — | — | — | — | — | — | — | — | — |
37 .6
GBP
|
12. 3
GBP
|
— | — | — | — | — | — | — | — | — |
| Income tax relating to change in value of foreign currency basis spreads included in other comprehensive income | — | — | — | — | — | — | — | — | — |
7. 7
GBP
|
11 .7
GBP
|
— | — | — | — | — | — | — | — | — |
| Other comprehensive income |
2 .6
GBP
|
9. 6
GBP
|
8,700,000
GBP
|
28 .9
GBP
|
–
GBP
|
1 2 7.1
GBP
|
— |
–
GBP
|
— |
82 . 5
GBP
|
5 6 . 3
GBP
|
1 .1
GBP
|
— |
9. 3
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
— |
41 . 6
GBP
|
89 .7
GBP
|
| Comprehensive income |
3 .1
GBP
|
9. 6
GBP
|
8,700,000
GBP
|
108,600,000
GBP
|
–
GBP
|
1 2 7.1
GBP
|
— |
–
GBP
|
— |
3. 3
GBP
|
2 14. 2
GBP
|
15 6 . 8
GBP
|
— |
9. 3
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
— |
41 .6
GBP
|
89. 7
GBP
|
| Comprehensive income attributable to [abstract] | ||||||||||||||||||||
| Comprehensive income, attributable to owners of parent | — | — | — | — | — | — | — | — | — |
0. 2
GBP
|
2 14. 2
GBP
|
— | — | — | — | — | — | — | — | — |
| Comprehensive income, attributable to non-controlling interests | — | — | — | — | — | — | — | — | — |
3 .1
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — |