Subclassifications Of Assets, Liabilities And Equities [Abstract]
| Concept |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-06-15 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
|---|---|---|---|---|---|---|---|
| Subclassifications of assets, liabilities and equities [abstract] | |||||||
| Property, plant and equipment [abstract] | |||||||
| Property, plant and equipment |
350,000,000
GBP
|
— | — | — |
428,000,000
GBP
|
— | — |
| Intangible assets and goodwill [abstract] | |||||||
| Intangible assets other than goodwill [abstract] | |||||||
| Intangible assets other than goodwill |
2,089,000,000
GBP
|
— | — | — |
1,950,000,000
GBP
|
— | — |
| Goodwill |
2,072,000,000
GBP
|
— | — | — |
1,741,000,000
GBP
|
— | — |
| Investment property [abstract] | |||||||
| Investment property |
5,899,000,000
GBP
|
— | — | — |
7,003,000,000
GBP
|
— | — |
| Investments accounted for using equity method [abstract] | |||||||
| Investments in associates accounted for using equity method |
41,000,000
GBP
|
— | — | — |
118,000,000
GBP
|
— | — |
| Investments in joint ventures accounted for using equity method |
1,933,000,000
GBP
|
— | — | — |
1,855,000,000
GBP
|
— | — |
| Trade and other receivables [abstract] | |||||||
| Trade and other receivables |
6,043,000,000
GBP
|
— | — | — |
6,088,000,000
GBP
|
— | — |
| Categories of financial assets [abstract] | |||||||
| Financial assets |
224,086,000,000
GBP
|
— | — | — |
264,961,000,000
GBP
|
— | — |
| Cash and cash equivalents [abstract] | |||||||
| Cash and cash equivalents |
22,505,000,000
GBP
|
— | — | — |
12,485,000,000
GBP
|
— | — |
| Miscellaneous assets [abstract] | |||||||
| Net defined benefit asset |
1,234,000,000
GBP
|
— | — | — |
2,769,000,000
GBP
|
— | — |
| Borrowings [abstract] | |||||||
| Borrowings |
6,755,000,000
GBP
|
— | — |
500,000,000
GBP
|
7,344,000,000
GBP
|
— | — |
| Borrowings, by type [abstract] | |||||||
| Notes and debentures issued |
496,000,000
GBP
|
— | — | — |
—
GBP
|
— | — |
| Miscellaneous liabilities [abstract] | |||||||
| Investment contracts liabilities |
158,999,000,000
GBP
|
— | — | — |
172,452,000,000
GBP
|
— | — |
| Other liabilities |
2,844,000,000
GBP
|
— | — | — |
2,959,000,000
GBP
|
— | — |
| Issued capital [abstract] | |||||||
| Issued capital |
1,124,000,000
GBP
|
924,000,000
GBP
|
200,000,000
GBP
|
— |
1,141,000,000
GBP
|
941,000,000
GBP
|
200,000,000
GBP
|
| Retained earnings [abstract] | |||||||
| Retained earnings |
327,000,000
GBP
|
— | — | — |
7,556,000,000
GBP
|
— | — |
| Accumulated other comprehensive income [abstract] | |||||||
| Reserve of exchange differences on translation |
511,000,000
GBP
|
— | — | — |
314,000,000
GBP
|
— | — |
| Miscellaneous equity [abstract] | |||||||
| Capital redemption reserve |
3,855,000,000
GBP
|
— | — | — |
86,000,000
GBP
|
— | — |
| Merger reserve |
5,224,000,000
GBP
|
— | — | — |
8,974,000,000
GBP
|
— | — |
| Capital reserve |
10,342,000,000
GBP
|
— | — | — |
10,308,000,000
GBP
|
— | — |
| Net assets (liabilities) [abstract] | |||||||
| Assets |
315,316,000,000
GBP
|
— | — | — |
358,474,000,000
GBP
|
— | — |
| Liabilities |
302,421,000,000
GBP
|
— | — | — |
339,020,000,000
GBP
|
— | — |
| Assets less current liabilities [abstract] |