Statement Of Cash Flows [Abstract]
| Concept |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
As at 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 |
As at 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 cash flows [abstract] | ||||||||||||||||||||
| Cash flows from (used in) operating activities [abstract] | ||||||||||||||||||||
| Profit (loss) |
15 4
GBP
|
–
GBP
|
1, 75 8
GBP
|
— |
–
GBP
|
–
GBP
|
1 ,9 12
GBP
|
–
GBP
|
1, 912
GBP
|
1, 7 5 8
GBP
|
1, 3 71
GBP
|
1, 2 9 9
GBP
|
–
GBP
|
— |
–
GBP
|
72,000,000
GBP
|
–
GBP
|
1, 2 9 9
GBP
|
–
GBP
|
1, 3 71
GBP
|
| Adjustments to reconcile profit (loss) [abstract] | ||||||||||||||||||||
| Adjustments for income tax expense | — | — | — | — | — | — | — | — |
19 8
GBP
|
— |
225,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Adjustments for decrease (increase) in inventories | — | — | — | — | — | — | — | — |
54,000,000
GBP
|
— |
24,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Adjustments for provisions | — | — | — | — | — | — | — | — |
66,000,000
GBP
|
— |
3 0
GBP
|
— | — | — | — | — | — | — | — | — |
| Adjustments for share-based payments | — | — | — | — | — | — | — | — |
92,000,000
GBP
|
— |
74,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Adjustments for fair value losses (gains) | — | — | — | — | — | — | — | — |
–
GBP
|
— |
6,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Adjustments for losses (gains) on disposal of non-current assets | — | — | — | — | — | — | — | — |
1 9 2
GBP
|
— |
25,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Cash flows from (used in) operating activities | — | — | — | — | — | — | — | — |
2 , 4 47
GBP
|
— |
1 ,1 6 6
GBP
|
— | — | — | — | — | — | — | — | — |
| Cash flows from (used in) investing activities [abstract] | ||||||||||||||||||||
| Cash flows from losing control of subsidiaries or other businesses, classified as investing activities | — | — | — | — | — | — | — | — |
215,000,000
GBP
|
— |
5,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Cash flows used in obtaining control of subsidiaries or other businesses, classified as investing activities | — | — | — | — | — | — | — | — |
3 0
GBP
|
— |
1, 70 6
GBP
|
— | — | — | — | — | — | — | — | — |
| Purchase of intangible assets, classified as investing activities | — | — | — | — | — | — | — | — |
96,000,000
GBP
|
— |
92,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Dividends received, classified as investing activities | — | — | — | — | — | — | — | — |
57,000,000
GBP
|
— |
27,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Interest received, classified as investing activities | — | — | — | — | — | — | — | — |
23,000,000
GBP
|
— |
19,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Cash flows from (used in) investing activities | — | — | — | — | — | — | — | — |
66,000,000
GBP
|
— |
2,03 7
GBP
|
— | — | — | — | — | — | — | — | — |
| Cash flows from (used in) financing activities [abstract] | ||||||||||||||||||||
| Proceeds from changes in ownership interests in subsidiaries that do not result in loss of control | — | — | — | — | — | — | — | — |
28,000,000
GBP
|
— |
27,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Payments to acquire or redeem entity's shares | — | — | — | — | — | — | — | — |
36 8
GBP
|
— |
–
GBP
|
— | — | — | — | — | — | — | — | — |
| Proceeds from borrowings, classified as financing activities | — | — | — | — | — | — | — | — |
–
GBP
|
— |
2,666,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Repayments of borrowings, classified as financing activities | — | — | — | — | — | — | — | — |
367,000,000
GBP
|
— |
506,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Payments of lease liabilities, classified as financing activities | — | — | — | — | — | — | — | — |
2 17
GBP
|
— |
236,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Interest paid, classified as financing activities | — | — | — | — | — | — | — | — |
247,000,000
GBP
|
— |
2 27
GBP
|
— | — | — | — | — | — | — | — | — |
| Cash flows from (used in) financing activities | — | — | — | — | — | — | — | — |
2, 256
GBP
|
— |
973,000,000
GBP
|
— | — | — | — | — | — | — | — | — |
| Increase (decrease) in cash and cash equivalents before effect of exchange rate changes | — | — | — | — | — | — | — | — |
257,000,000
GBP
|
— |
10 2
GBP
|
— | — | — | — | — | — | — | — | — |
| Effect of exchange rate changes on cash and cash equivalents [abstract] | ||||||||||||||||||||
| Effect of exchange rate changes on cash and cash equivalents | — | — | — | — | — | — | — | — |
7,000,000
GBP
|
— |
2 2
GBP
|
— | — | — | — | — | — | — | — | — |
| Cash and cash equivalents | — | — | — |
2 , 9 17
GBP
|
— | — | — | — | — | — | — | — | — |
2,76 8
GBP
|
— | — | — | — | — | — |