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 |
2021-01-01 to 2021-12-31 |
|---|---|---|---|---|---|---|
| Statement of cash flows [abstract] | ||||||
| Cash flows from (used in) operating activities [abstract] | ||||||
| Income taxes paid (refund), classified as operating activities |
445,000,000
GBP
|
— | — |
324,000,000
GBP
|
— |
310,000,000
GBP
|
| Cash flows from (used in) operating activities |
2,100,000,000
GBP
|
— | — |
2,063,000,000
GBP
|
— |
1,356,000,000
GBP
|
| Cash flows from (used in) investing activities [abstract] | ||||||
| Cash flows used in obtaining control of subsidiaries or other businesses, classified as investing activities |
71,000,000
GBP
|
— | — |
—
GBP
|
— |
—
GBP
|
| Proceeds from sales of property, plant and equipment, classified as investing activities |
—
GBP
|
— | — |
—
GBP
|
— |
12,000,000
GBP
|
| Purchase of property, plant and equipment, classified as investing activities |
234,000,000
GBP
|
— | — |
304,000,000
GBP
|
— |
228,000,000
GBP
|
| Proceeds from sales of intangible assets, classified as investing activities |
246,000,000
GBP
|
— | — |
36,000,000
GBP
|
— |
137,000,000
GBP
|
| Purchase of intangible assets, classified as investing activities |
102,000,000
GBP
|
— | — |
24,000,000
GBP
|
— |
70,000,000
GBP
|
| Interest received, classified as investing activities |
27,000,000
GBP
|
— | — |
19,000,000
GBP
|
— |
16,000,000
GBP
|
| Cash flows from (used in) investing activities |
134,000,000
GBP
|
— | — |
8,784,000,000
GBP
|
— |
33,000,000
GBP
|
| Cash flows from (used in) financing activities [abstract] | ||||||
| Proceeds from borrowings, classified as financing activities |
—
GBP
|
— | — |
11,004,000,000
GBP
|
— |
8,000,000
GBP
|
| Repayments of borrowings, classified as financing activities |
553,000,000
GBP
|
— | — |
1,518,000,000
GBP
|
— |
—
GBP
|
| Payments of lease liabilities, classified as financing activities |
55,000,000
GBP
|
— | — |
45,000,000
GBP
|
— |
38,000,000
GBP
|
| Interest paid, classified as financing activities |
404,000,000
GBP
|
— | — |
163,000,000
GBP
|
— |
15,000,000
GBP
|
| Other inflows (outflows) of cash, classified as financing activities |
72,000,000
GBP
|
— | — |
345,000,000
GBP
|
— |
12,000,000
GBP
|
| Cash flows from (used in) financing activities |
1,568,000,000
GBP
|
— | — |
6,911,000,000
GBP
|
— |
1,236,000,000
GBP
|
| Effect of exchange rate changes on cash and cash equivalents [abstract] | ||||||
| Effect of exchange rate changes on cash and cash equivalents |
15,000,000
GBP
|
— | — |
15,000,000
GBP
|
— |
4,000,000
GBP
|
| Cash and cash equivalents | — |
1,044,000,000
GBP
|
684,000,000
GBP
|
— |
414,000,000
GBP
|
— |