Analysis Of Income And Expense [Abstract]
| Concept | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2021-01-01 to 2021-12-31 | 2021-01-01 to 2021-12-31 | 2021-01-01 to 2021-12-31 | 2021-01-01 to 2021-12-31 | 2021-01-01 to 2021-12-31 | 2021-01-01 to 2021-12-31 | 2021-01-01 to 2021-12-31 | 2021-01-01 to 2021-12-31 | 2021-01-01 to 2021-12-31 | 2021-01-01 to 2021-12-31 | 2021-01-01 to 2021-12-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Analysis of income and expense [abstract] | ||||||||||||||||||||||
| Material income and expense [abstract] | ||||||||||||||||||||||
| Gains (losses) on disposals of investment properties [abstract] | ||||||||||||||||||||||
| Gains (losses) on disposals of investment properties | — | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                250,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | 
                                                250,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | 
| Finance income (cost) | — | 
                                                801,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                801,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                851,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | 
                                                851,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | 
| Comprehensive income, continuing and discontinued operations [abstract] | ||||||||||||||||||||||
| Comprehensive income | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                7 ,116
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                7, 116
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                11,944,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                11,944,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
| Comprehensive income attributable to owners of parent, continuing and discontinued operations [abstract] | ||||||||||||||||||||||
| Comprehensive income, attributable to owners of parent | — | 
                                                7 ,116
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | 
                                                10,381,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                3,265,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                2,939,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | 
                                                9,005,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — | — | — | 
                                                11,944,000
                                                
                                                    
                                                        GBP
                                                    
                                                
                                             | — |