Statement Of Cash Flows [Abstract]
| Concept |
2023-01-01 to 2023-12-31 |
2022-01-01 to 2022-12-31 |
|---|---|---|
| Statement of cash flows [abstract] | ||
| Cash flows from (used in) investing activities [abstract] | ||
| Purchase of interests in investments accounted for using equity method |
2,000,000
GBP
|
20,000,000
GBP
|
| Proceeds from sales of investments accounted for using equity method |
–
GBP
|
6,000,000
GBP
|
| Purchase of financial instruments, classified as investing activities |
445,000,000
GBP
|
297,000,000
GBP
|
| Proceeds from sales or maturity of financial instruments, classified as investing activities |
1,029,000,000
GBP
|
1,633,000,000
GBP
|
| Cash flows from (used in) financing activities [abstract] | ||
| Repayments of bonds, notes and debentures |
–
GBP
|
92,000,000
GBP
|