Subclassifications Of Assets, Liabilities And Equities [Abstract]
| Concept |
As at 2024-12-31 |
As at 2024-01-01 |
As at 2023-12-31 |
As at 2023-01-01 |
|---|---|---|---|---|
| Subclassifications of assets, liabilities and equities [abstract] | ||||
| Property, plant and equipment [abstract] | ||||
| Property, plant and equipment |
7 .8
GBP
|
— |
8,400,000
GBP
|
— |
| Intangible assets and goodwill [abstract] | ||||
| Intangible assets and goodwill |
87 .2
GBP
|
— |
96,400,000
GBP
|
— |
| Investment property [abstract] | ||||
| Investment property |
91,700,000
GBP
|
— |
88,100,000
GBP
|
— |
| Categories of financial assets [abstract] | ||||
| Held-to-maturity investments |
34. 3
GBP
|
— |
32 .5
GBP
|
— |
| Cash and cash equivalents [abstract] | ||||
| Cash and cash equivalents |
138,000,000
GBP
|
145,900,000
GBP
|
146,000,000
GBP
|
204,600,000
GBP
|
| Miscellaneous assets [abstract] | ||||
| Derivative financial assets |
1 2,1 16 .7
GBP
|
— |
1 1,45 6.1
GBP
|
— |
| Classes of other provisions [abstract] | ||||
| Other provisions [abstract] | ||||
| Other provisions |
20,300,000
GBP
|
— |
23. 2
GBP
|
— |
| Borrowings [abstract] | ||||
| Borrowings |
204 .8
GBP
|
— |
207 .9
GBP
|
— |
| Borrowings, by type [abstract] | ||||
| Trade and other payables [abstract] | ||||
| Accruals and deferred income including contract liabilities [abstract] | ||||
| Deferred income including contract liabilities [abstract] | ||||
| Deferred income other than contract liabilities |
1,300,000
GBP
|
— |
2,800,000
GBP
|
— |
| Miscellaneous current liabilities [abstract] | ||||
| Other current liabilities |
129,700,000
GBP
|
— |
13 1.7
GBP
|
— |
| Miscellaneous liabilities [abstract] | ||||
| Derivative financial liabilities |
600,000
GBP
|
— |
4 .4
GBP
|
— |
| Investment contracts liabilities |
6,1 1 6.7
GBP
|
— |
5,872 .3
GBP
|
— |
| Issued capital [abstract] | ||||
| Issued capital |
7 .5
GBP
|
— |
7,500,000
GBP
|
— |
| Retained earnings [abstract] | ||||
| Retained earnings |
1 36.5
GBP
|
— |
167,000,000
GBP
|
— |
| Miscellaneous equity [abstract] | ||||
| Merger reserve |
36,300,000
GBP
|
— |
36,300,000
GBP
|
— |
| Net assets (liabilities) [abstract] | ||||
| Assets |
12 ,75 5 .1
GBP
|
— |
12 ,12 9 .7
GBP
|
— |
| Liabilities |
1 2 , 4 4 0.7
GBP
|
— |
1 1 ,769.9
GBP
|
— |
| Assets (liabilities) |
314,400,000
GBP
|
— |
359,900,000
GBP
|
— |
| Assets less current liabilities [abstract] |