Disclosure Of Fair Value Measurement [Text Block]
| Concept | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 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 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | 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 | 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 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 | As at 2022-12-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Disclosure of fair value measurement [text block] | — | — | — | — | — | — | — | — | 
                                                A. Investment properties – residential
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Disclosure of fair value measurement of assets [text block] | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Disclosure of fair value measurement of assets [abstract] | |||||||||||||||||||||||||||||||||
| Disclosure of fair value measurement of assets [line items] | |||||||||||||||||||||||||||||||||
| Assets | — | — | — | — | — | — | — | — | — | — | — | 
                                                6,887,153,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                7,716,787,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Reconciliation of changes in fair value measurement, assets [abstract] | |||||||||||||||||||||||||||||||||
| Disclosure of fair value measurement of equity [text block] | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Disclosure of fair value measurement of equity [abstract] | |||||||||||||||||||||||||||||||||
| Disclosure of fair value measurement of equity [line items] | |||||||||||||||||||||||||||||||||
| Equity | 
                                                145,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                716,707,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1,352,066,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1,775,304,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                188,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                238,444,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                16,949,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1,326,734,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | 
                                                315,746,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                146,239,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1,565,178,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                42,404,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                145,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                2,278,087,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                271,260,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1,873,598,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                188,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                5,305,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                228,856,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                145,751,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                315,746,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1,913,063,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                903,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                495,951,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1,844,765,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                621,651,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                146,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                10,772,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1,417,112,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                133,569,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                315,746,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
| Reconciliation of changes in fair value measurement, entity's own equity instruments [abstract] |