Analysis Of Income And Expense [Abstract]
| Concept | 
                                    
                                        2023-04-01 to 2024-03-31  | 
                            
                                
                                    
                                        2023-04-01 to 2024-03-31  | 
                            
                                
                                    
                                        2023-04-01 to 2024-03-31  | 
                            
                                
                                    
                                        2023-04-01 to 2024-03-31  | 
                            
                                
                                    
                                        2023-04-01 to 2024-03-31  | 
                            
                                
                                    
                                        2023-04-01 to 2024-03-31  | 
                            
                                
                                    
                                        2023-04-01 to 2024-03-31  | 
                            
                                
                                    
                                        2023-04-01 to 2024-03-31  | 
                            
                                
                                    
                                        2023-04-01 to 2024-03-31  | 
                            
                                
                                    
                                        2022-04-01 to 2023-03-31  | 
                            
                                
                                    
                                        2022-04-01 to 2023-03-31  | 
                            
                                
                                    
                                        2022-04-01 to 2023-03-31  | 
                            
                                
                                    
                                        2022-04-01 to 2023-03-31  | 
                            
                                
                                    
                                        2022-04-01 to 2023-03-31  | 
                            
                                
                                    
                                        2022-04-01 to 2023-03-31  | 
                            
                                
                                    
                                        2022-04-01 to 2023-03-31  | 
                            
                                
                                    
                                        2022-04-01 to 2023-03-31  | 
                            
                                
                                    
                                        2022-04-01 to 2023-03-31  | 
                            
                        
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Analysis of income and expense [abstract] | ||||||||||||||||||
| Revenue [abstract] | ||||||||||||||||||
| Revenue | — | — | — | — | — | 
                                        
                                             
                                                96,624,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                100,614,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Material income and expense [abstract] | ||||||||||||||||||
| Finance income (cost) | — | — | — | — | — | 
                                        
                                             
                                                4,589,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                305,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Miscellaneous other comprehensive income [abstract] | ||||||||||||||||||
| Other comprehensive income, net of tax, exchange differences on translation of foreign operations and hedges of net investments in foreign operations [abstract] | ||||||||||||||||||
| Other comprehensive income, net of tax, exchange differences on translation of foreign operations | — | — | — | — | — | 
                                        
                                             
                                                1,021,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                197,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Share of profit (loss) of associates and joint ventures accounted for using equity method [abstract] | ||||||||||||||||||
| Share of profit (loss) of joint ventures accounted for using equity method | — | — | — | — | — | 
                                        
                                             
                                                1,090,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                2,665,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Comprehensive income, continuing and discontinued operations [abstract] | ||||||||||||||||||
| Comprehensive income | 
                                        
                                             
                                                –
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                1,021,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                296,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                7,039,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                –
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                5,722,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                –
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                –
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                –
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                –
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                635,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                –
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                –
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                –
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                16,238,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                197,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                –
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                15,800,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Comprehensive income attributable to owners of parent, continuing and discontinued operations [abstract] | ||||||||||||||||||
| Comprehensive income, attributable to owners of parent | — | — | — | — | — | 
                                        
                                             
                                                5,722,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                15,800,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             
                                        
                                     |