Statement Of Cash Flows [Abstract]
| Concept |
As at 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
2020-01-01 to 2020-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
|---|---|---|---|---|---|---|---|
| Statement of cash flows [abstract] | |||||||
| Cash flows from (used in) operating activities [abstract] | |||||||
| Profit (loss) | — |
263,200,000
GBP
|
263,200,000
GBP
|
185,900,000
GBP
|
— |
186,300,000
GBP
|
400,000
GBP
|
| Cash flows from (used in) operations | — |
668,500,000
GBP
|
— | — | — |
628,800,000
GBP
|
— |
| Interest paid, classified as operating activities | — |
41,600,000
GBP
|
— | — | — |
48,600,000
GBP
|
— |
| Interest received, classified as operating activities | — |
5,200,000
GBP
|
— | — | — |
7. 6
GBP
|
— |
| Cash flows from (used in) operating activities | — |
563,200,000
GBP
|
— | — | — |
523,400,000
GBP
|
— |
| Cash flows from (used in) investing activities [abstract] | |||||||
| Cash flows from losing control of subsidiaries or other businesses, classified as investing activities | — | — | — | — | — |
2,200,000
GBP
|
— |
| Cash flows used in obtaining control of subsidiaries or other businesses, classified as investing activities | — |
463. 1
GBP
|
— | — | — |
194. 7
GBP
|
— |
| Proceeds from sales of property, plant and equipment, classified as investing activities | — |
7. 4
GBP
|
— | — | — |
6,300,000
GBP
|
— |
| Purchase of property, plant and equipment, classified as investing activities | — |
127 .8
GBP
|
— | — | — |
129,900,000
GBP
|
— |
| Purchase of intangible assets, classified as investing activities | — |
32. 1
GBP
|
— | — | — |
22,600,000
GBP
|
— |
| Cash payments for futures contracts, forward contracts, option contracts and swap contracts, classified as investing activities | — |
19. 1
GBP
|
— | — | — |
23. 7
GBP
|
— |
| Dividends received, classified as investing activities | — |
3,900,000
GBP
|
— | — | — |
11. 7
GBP
|
— |
| Cash flows from (used in) investing activities | — |
441. 1
GBP
|
— | — | — |
497 .5
GBP
|
— |
| Cash flows from (used in) financing activities [abstract] | |||||||
| Payments to acquire or redeem entity's shares | — |
9,400,000
GBP
|
— | — | — | — | — |
| Proceeds from borrowings, classified as financing activities | — |
4 .7
GBP
|
— | — | — |
1, 714.8
GBP
|
— |
| Repayments of borrowings, classified as financing activities | — |
166,600,000
GBP
|
— | — | — |
1,352,200,000
GBP
|
— |
| Payments of lease liabilities, classified as financing activities | — |
88,000,000
GBP
|
— | — | — |
85,400,000
GBP
|
— |
| Cash flows from (used in) financing activities | — |
417 . 1
GBP
|
— | — | — |
253,500,000
GBP
|
— |
| Effect of exchange rate changes on cash and cash equivalents [abstract] | |||||||
| Effect of exchange rate changes on cash and cash equivalents | — |
13,900,000
GBP
|
— | — | — |
2,500,000
GBP
|
— |
| Increase (decrease) in cash and cash equivalents after effect of exchange rate changes | — |
295,000,000
GBP
|
— | — | — |
279,400,000
GBP
|
— |
| Cash and cash equivalents |
668,400,000
GBP
|
— | — | — |
1,949,500,000
GBP
|
— | — |