Statement Of Cash Flows [Abstract]
| Concept |
2023-01-01 to 2023-12-31 |
As at 2023-12-31 |
As at 2022-12-31 |
2022-01-01 to 2022-12-31 |
As at 2021-12-31 |
|---|---|---|---|---|---|
| Statement of cash flows [abstract] | |||||
| Cash flows from (used in) operating activities [abstract] | |||||
| Cash flows from (used in) operations |
2,137,000,000
GBP
|
— | — |
1,698,000,000
GBP
|
— |
| Income taxes paid (refund), classified as operating activities |
26,000,000
GBP
|
— | — |
22,000,000
GBP
|
— |
| Cash flows from (used in) operating activities |
2,111,000,000
GBP
|
— | — |
1,676,000,000
GBP
|
— |
| Cash flows from (used in) investing activities [abstract] | |||||
| Cash flows used in obtaining control of subsidiaries or other businesses, classified as investing activities |
–
GBP
|
— | — |
5,000,000
GBP
|
— |
| Proceeds from sales of property, plant and equipment, classified as investing activities |
1,000,000
GBP
|
— | — |
–
GBP
|
— |
| Purchase of property, plant and equipment, classified as investing activities |
1,000,000
GBP
|
— | — |
3,000,000
GBP
|
— |
| Cash flows from (used in) investing activities |
1,909,000,000
GBP
|
— | — |
1,502,000,000
GBP
|
— |
| Cash flows from (used in) financing activities [abstract] | |||||
| Payments to acquire or redeem entity's shares |
–
GBP
|
— | — |
328,000,000
GBP
|
— |
| Payments of lease liabilities, classified as financing activities |
9,000,000
GBP
|
— | — |
11,000,000
GBP
|
— |
| Interest paid, classified as financing activities |
3,000,000
GBP
|
— | — |
3,000,000
GBP
|
— |
| Cash flows from (used in) financing activities |
123,000,000
GBP
|
— | — |
461,000,000
GBP
|
— |
| Increase (decrease) in cash and cash equivalents before effect of exchange rate changes |
79,000,000
GBP
|
— | — |
287,000,000
GBP
|
— |
| Effect of exchange rate changes on cash and cash equivalents [abstract] | |||||
| Effect of exchange rate changes on cash and cash equivalents |
2,000,000
GBP
|
— | — |
5,000,000
GBP
|
— |
| Cash and cash equivalents | — |
1,859,000,000
GBP
|
1,782,000,000
GBP
|
— |
2,064,000,000
GBP
|