Statement Of Changes In Equity [Abstract]
| Concept | 
                                    
                                        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  | 
                            
                                
                                    
                                        As at 2024-12-31  | 
                            
                                
                                    
                                        As at 2024-12-31  | 
                            
                                
                                    
                                        As at 2024-12-31  | 
                            
                                
                                    
                                        As at 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  | 
                            
                                
                                    
                                        As at 2024-12-31  | 
                            
                                
                                    
                                        2024-01-01 to 2024-12-31  | 
                            
                                
                                    
                                        2024-01-01 to 2024-12-31  | 
                            
                                
                                    
                                        As at 2024-12-31  | 
                            
                                
                                    
                                        As at 2024-12-31  | 
                            
                                
                                    
                                        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  | 
                            
                                
                                    
                                        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  | 
                            
                                
                                    
                                        As at 2023-12-31  | 
                            
                                
                                    
                                        2023-01-01 to 2023-12-31  | 
                            
                                
                                    
                                        2023-01-01 to 2023-12-31  | 
                            
                                
                                    
                                        As at 2023-12-31  | 
                            
                                
                                    
                                        As at 2023-12-31  | 
                            
                                
                                    
                                        As at 2023-12-31  | 
                            
                                
                                    
                                        As at 2023-12-31  | 
                            
                                
                                    
                                        As at 2023-12-31  | 
                            
                                
                                    
                                        As at 2023-12-31  | 
                            
                                
                                    
                                        2023-01-01 to 2023-12-31  | 
                            
                                
                                    
                                        As at 2022-12-31  | 
                            
                                
                                    
                                        As at 2022-12-31  | 
                            
                                
                                    
                                        As at 2022-12-31  | 
                            
                                
                                    
                                        As at 2022-12-31  | 
                            
                                
                                    
                                        As at 2022-12-31  | 
                            
                                
                                    
                                        As at 2022-12-31  | 
                            
                                
                                    
                                        As at 2022-12-31  | 
                            
                                
                                    
                                        As at 2022-12-31  | 
                            
                                
                                    
                                        As at 2022-12-31  | 
                            
                        
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||||||||||||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | |||||||||||||||||||||||||||||||||||||||||||||
| Equity | — | — | — | 
                                        
                                             
                                                13,660,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                604,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                786,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                2,725,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
                                        
                                             
                                                10,824,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
                                        
                                             
                                                71,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                10,824,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
                                        
                                             
                                                9,587,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                12,781,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
                                        
                                             
                                                604,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                1,062,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                2,725,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                9,587,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                11,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                6,800,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                549,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                846,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                6,800,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                10,514,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                3,366,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                51,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Changes in equity [abstract] | |||||||||||||||||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||||||||||||||||||||||||||
| Profit (loss) | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                988,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | 
                                        
                                             
                                                988,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                71,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                1,059,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
                                        
                                             
                                                266,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                228,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                38,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                228,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | 
| Other comprehensive income | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                312,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                276,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | 
                                        
                                             
                                                46,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                312,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                82,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
                                        
                                             
                                                180,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                180,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                4,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                216,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | 
                                        
                                             
                                                40,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | 
| Comprehensive income | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                1,300,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                276,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | 
                                        
                                             
                                                942,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                71,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                1,371,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                82,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
                                        
                                             
                                                86,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                48,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                38,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                224,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                216,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | 
                                        
                                             
                                                40,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | 
| Dividends recognised as distributions to owners | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                32,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                32,000,000
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        DKK
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — |