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 |
As at 2020-12-31 |
|---|---|---|---|---|---|---|---|
| Statement of cash flows [abstract] | |||||||
| Cash flows from (used in) operating activities [abstract] | |||||||
| Dividends received, classified as operating activities |
15,000,000
GBP
|
— | — |
7,000,000
GBP
|
— |
—
GBP
|
— |
| Interest paid, classified as operating activities |
17,267,000,000
GBP
|
— | — |
5,284,000,000
GBP
|
— |
2,919,000,000
GBP
|
— |
| Interest received, classified as operating activities |
19,288,000,000
GBP
|
— | — |
7,668,000,000
GBP
|
— |
4,285,000,000
GBP
|
— |
| Income taxes paid (refund), classified as operating activities |
140,000,000
GBP
|
— | — |
845,000,000
GBP
|
— |
581,000,000
GBP
|
— |
| Cash flows from (used in) operating activities |
3,630,000,000
GBP
|
— | — |
32,190,000,000
GBP
|
— |
15,303,000,000
GBP
|
— |
| Cash flows from (used in) investing activities [abstract] | |||||||
| Cash flows used in obtaining control of subsidiaries or other businesses, classified as investing activities |
1,161,000,000
GBP
|
— | — |
29,000,000
GBP
|
— |
85,000,000
GBP
|
— |
| Purchase of intangible assets, classified as investing activities |
125,000,000
GBP
|
— | — |
28,000,000
GBP
|
— |
45,000,000
GBP
|
— |
| Cash flows from (used in) investing activities |
12,800,000,000
GBP
|
— | — |
7,186,000,000
GBP
|
— |
6,059,000,000
GBP
|
— |
| Cash flows from (used in) financing activities [abstract] | |||||||
| Cash flows from (used in) financing activities |
169,000,000
GBP
|
— | — |
1,902,000,000
GBP
|
— |
631,000,000
GBP
|
— |
| Increase (decrease) in cash and cash equivalents before effect of exchange rate changes |
9,001,000,000
GBP
|
— | — |
41,278,000,000
GBP
|
— |
20,731,000,000
GBP
|
— |
| Effect of exchange rate changes on cash and cash equivalents [abstract] | |||||||
| Effect of exchange rate changes on cash and cash equivalents |
3,869,000,000
GBP
|
— | — |
7,706,000,000
GBP
|
— |
5,112,000,000
GBP
|
— |
| Cash and cash equivalents | — |
177,037,000,000
GBP
|
189,907,000,000
GBP
|
— |
140,923,000,000
GBP
|
— |
125,304,000,000
GBP
|