Analysis Of Income And Expense [Abstract]
| 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 | 2024-01-01 to 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 | 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 | 2023-01-01 to 2023-12-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Analysis of income and expense [abstract] | ||||||||||||||||
| Material income and expense [abstract] | ||||||||||||||||
| Research and development expense | — | 
                                                2 282
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                1 930
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | 
| Finance income (cost) | — | 
                                                946,000,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                948,000,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | 
| Sales and marketing expense | — | 
                                                4 250
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                3 959
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | 
| Share of profit (loss) of associates and joint ventures accounted for using equity method [abstract] | ||||||||||||||||
| Share of profit (loss) of associates and joint ventures accounted for using equity method | — | 
                                                20,000,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                15,000,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | 
| Income tax relating to components of other comprehensive income [abstract] | ||||||||||||||||
| Income tax relating to components of other comprehensive income that will be reclassified to profit or loss | — | 
                                                8,000,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                17,000,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | 
| Comprehensive income, continuing and discontinued operations [abstract] | ||||||||||||||||
| Comprehensive income | 
                                                28,000,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                10 345
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                29,000,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                1 456
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                10 317
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                8 890
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                –
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                1 356
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                7 716
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                10,000,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                64,000,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                9 126
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
                                                7 706
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | 
| Comprehensive income attributable to owners of parent, continuing and discontinued operations [abstract] | ||||||||||||||||
| Comprehensive income, attributable to owners of parent | — | 
                                                10 317
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                7 706
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | 
| Comprehensive income attributable to non-controlling interests, continuing and discontinued operations [abstract] | ||||||||||||||||
| Comprehensive income, attributable to non-controlling interests | — | 
                                                28,000,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                10,000,000
                                                
                                                    
                                                        SEK
                                                    
                                                
                                             | — | — | — | — |