Disclosure Of Effect Of Changes In Foreign Exchange Rates [Text Block]
| Concept | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | As at 2024-12-31 | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | As at 2023-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Disclosure of effect of changes in foreign exchange rates [text block] | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Disclosure of information when currency is not exchangeable into another currency [text block] | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Disclosure of information when foreign operation’s functional currency is not exchangeable into presentation currency [text block] | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Disclosure of summarised financial information about foreign operation [text block] | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Disclosure of summarised financial information about foreign operation [abstract] | ||||||||||||||||
| Disclosure of summarised financial information about foreign operation [line items] | ||||||||||||||||
| Non-current assets | — | — | — | — | — | 
                                                157 .6
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | 
                                                279 .2
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | 
| Current assets | — | — | — | — | — | 
                                                188,700,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | 
                                                159 .8
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | 
| Non-current liabilities | — | — | — | — | — | 
                                                141,600,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | 
                                                143,500,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | 
| Current liabilities | — | — | — | — | — | 
                                                118,800,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | 
                                                65,700,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | 
| Revenue | 
                                                283,600,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                306. 9
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | 
| Profit (loss) from continuing operations | 
                                                147 .0
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                12. 1
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | 
| Profit (loss) from discontinued operations | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                66,000,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | 
| Profit (loss) | 
                                                147 .0
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                147 .0
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                78. 1
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                78. 1
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
| Other comprehensive income | 
                                                6,300,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                2 .5
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | 
                                                3,500,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                300,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                13. 1
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | 
                                                1,000,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                0 .1
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                12,200,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
| Comprehensive income | 
                                                153,300,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                2 .5
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | 
                                                3,500,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                147 .3
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                91,200,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | 
                                                1,000,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                78,000,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                12 .2
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             |