Statement Of Cash Flows [Abstract]
| Concept |
2024-01-01 to 2024-12-31 |
2024-01-01 to 2024-12-31 |
2024-01-01 to 2024-12-31 |
2024-01-01 to 2024-12-31 |
2024-01-01 to 2024-12-31 |
As at 2024-12-31 |
2024-01-01 to 2024-12-31 |
2024-01-01 to 2024-12-31 |
2023-01-01 to 2023-12-31 |
As at 2023-12-31 |
As at 2022-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of cash flows [abstract] | |||||||||||
| Cash flows from (used in) operating activities [abstract] | |||||||||||
| Profit (loss) |
34,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
— |
–
GBP
|
34,000,000
GBP
|
— | — | — |
| Cash flows from (used in) operations |
4,654,000,000
GBP
|
— | — | — | — | — | — | — |
2,137,000,000
GBP
|
— | — |
| Income taxes paid (refund), classified as operating activities |
69,000,000
GBP
|
— | — | — | — | — | — | — |
26,000,000
GBP
|
— | — |
| Cash flows from (used in) operating activities |
4,585,000,000
GBP
|
— | — | — | — | — | — | — |
2,111,000,000
GBP
|
— | — |
| Cash flows from (used in) investing activities [abstract] | |||||||||||
| Cash flows used in obtaining control of subsidiaries or other businesses, classified as investing activities |
6,000,000
GBP
|
— | — | — | — | — | — | — |
–
GBP
|
— | — |
| Proceeds from sales of property, plant and equipment, classified as investing activities |
–
GBP
|
— | — | — | — | — | — | — |
1,000,000
GBP
|
— | — |
| Purchase of property, plant and equipment, classified as investing activities |
8,000,000
GBP
|
— | — | — | — | — | — | — |
1,000,000
GBP
|
— | — |
| Cash flows from (used in) investing activities |
4,388,000,000
GBP
|
— | — | — | — | — | — | — |
1,909,000,000
GBP
|
— | — |
| Cash flows from (used in) financing activities [abstract] | |||||||||||
| Payments of lease liabilities, classified as financing activities |
8,000,000
GBP
|
— | — | — | — | — | — | — |
9,000,000
GBP
|
— | — |
| Interest paid, classified as financing activities |
2,000,000
GBP
|
— | — | — | — | — | — | — |
3,000,000
GBP
|
— | — |
| Cash flows from (used in) financing activities |
108,000,000
GBP
|
— | — | — | — | — | — | — |
123,000,000
GBP
|
— | — |
| Increase (decrease) in cash and cash equivalents before effect of exchange rate changes |
89,000,000
GBP
|
— | — | — | — | — | — | — |
79,000,000
GBP
|
— | — |
| Effect of exchange rate changes on cash and cash equivalents [abstract] | |||||||||||
| Effect of exchange rate changes on cash and cash equivalents |
1,000,000
GBP
|
— | — | — | — | — | — | — |
2,000,000
GBP
|
— | — |
| Cash and cash equivalents | — | — | — | — | — |
1,949,000,000
GBP
|
— | — | — |
1,859,000,000
GBP
|
1,782,000,000
GBP
|