Statement Of Cash Flows [Abstract]
| Concept |
As at 2021-12-31 |
2021-01-01 to 2021-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
|---|---|---|---|---|
| Statement of cash flows [abstract] | ||||
| Cash flows from (used in) operating activities [abstract] | ||||
| 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
|
— |