Statement Of Financial Position [Abstract]
| 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 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 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | |||||||||||||||||||||
| Assets [abstract] | |||||||||||||||||||||
| Non-current assets [abstract] | |||||||||||||||||||||
| Investment property | — | — | — | — | — | — | 
                                                91,100,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                91,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Deferred tax assets | — | — | — | — | — | — | 
                                                0
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                223,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Non-current assets | — | — | — | — | — | — | 
                                                92,364,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                92,530,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Current assets [abstract] | |||||||||||||||||||||
| Current tax assets, current | — | — | — | — | — | — | 
                                                143,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                116,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Cash and cash equivalents | — | — | — | — | — | — | 
                                                3,590,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                2,648,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                7,787,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | 
| Current assets | — | — | — | — | — | — | 
                                                5,354,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                9,591,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Assets | — | — | — | — | — | — | 
                                                97,718,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                102,121,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Equity and liabilities [abstract] | |||||||||||||||||||||
| Equity [abstract] | |||||||||||||||||||||
| Issued capital | — | — | — | — | — | — | 
                                                4,900,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                4,082,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Retained earnings | — | — | — | — | — | — | 
                                                10,696,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                11,193,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Share premium | — | — | — | — | — | — | 
                                                47,379,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                42,317,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Equity attributable to owners of parent | — | — | — | — | — | — | 
                                                62,988,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                57,605,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Non-controlling interests | — | — | — | — | — | — | 
                                                114,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                104,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Equity | 
                                                10,696,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                47,379,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                4,900,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                114,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                13,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                57,108,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                63,102,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                57,709,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                11,193,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                104,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                42,317,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                4,082,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                13,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                57,605,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                61,210,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                134,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                42,317,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                14,530,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                4,216,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                13,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                61,076,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
| Liabilities [abstract] | |||||||||||||||||||||
| Non-current liabilities [abstract] | |||||||||||||||||||||
| Deferred tax liabilities | — | — | — | — | — | — | 
                                                5,524,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                5,678,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Non-current liabilities | — | — | — | — | — | — | 
                                                32,793,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                38,915,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Current liabilities [abstract] | |||||||||||||||||||||
| Current liabilities | — | — | — | — | — | — | 
                                                1,823,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                5,497,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Equity and liabilities | — | — | — | — | — | — | 
                                                97,718,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                102,121,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — |