Analysis Of Income And Expense [Abstract]
| Concept | 
                                    
                                        2023-01-01 to 2023-12-31  | 
                            
                                
                                    
                                        2023-01-01 to 2023-12-31  | 
                            
                                
                                    
                                        2022-01-01 to 2022-12-31  | 
                            
                                
                                    
                                        2022-01-01 to 2022-12-31  | 
                            
                        
|---|---|---|---|---|
| Analysis of income and expense [abstract] | ||||
| Revenue [abstract] | ||||
| Revenue | — | 
                                        
                                             
                                                837  523
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                79 7    116
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Material income and expense [abstract] | ||||
| Finance income (cost) | — | 
                                        
                                             
                                                2 295
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                915,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Expenses by nature [abstract] | ||||
| Classes of employee benefits expense [abstract] | ||||
| Employee benefits expense | — | 
                                        
                                             
                                                398  430
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                369  066
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Depreciation, amortisation and impairment loss (reversal of impairment loss) recognised in profit or loss [abstract] | ||||
| Depreciation and amortisation expense [abstract] | ||||
| Depreciation and amortisation expense | — | 
                                        
                                             
                                                14   038
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                17   355
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Other expenses, by nature | — | 
                                        
                                             
                                                34 658
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                39  020
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Disclosure of attribution of expenses by nature to their function [text block] | — | — | — | — | 
| Disclosure of attribution of expenses by nature to their function [abstract] | ||||
| Disclosure of attribution of expenses by nature to their function [line items] | ||||
| Comprehensive income, continuing and discontinued operations [abstract] | ||||
| Comprehensive income | 
                                        
                                             
                                                84  0 41
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                84  0 41
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                68  224
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                68  224
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Comprehensive income attributable to owners of parent, continuing and discontinued operations [abstract] | ||||
| Comprehensive income, attributable to owners of parent | — | 
                                        
                                             
                                                84  0 41
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                68  224
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             
                                        
                                     |