Profit Or Loss [Abstract]
| Concept | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | 2024-01-01 to 2024-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | 2023-01-01 to 2023-12-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Profit or loss [abstract] | ||||||||||||||||||
| Profit (loss) [abstract] | ||||||||||||||||||
| Impairment loss (reversal of impairment loss) recognised in profit or loss | — | — | 
                                                5,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                5,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | 
| Profit (loss) from operating activities | — | — | 
                                                52,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                2,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | 
| Share of profit (loss) of associates and joint ventures accounted for using equity method | — | — | 
                                                1,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                25,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | 
| Tax expense (income) | — | — | 
                                                16,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                20,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | 
| Profit (loss) from continuing operations | — | — | 
                                                161,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                144,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | 
| Profit (loss) from discontinued operations | — | — | 
                                                121,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                141,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | 
| Profit (loss) | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                282,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                282,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                282,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                285,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                285,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                285,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
| Profit (loss), attributable to [abstract] | ||||||||||||||||||
| Profit (loss), attributable to owners of parent | — | — | 
                                                282,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                285,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | 
| Profit (loss), attributable to non-controlling interests | — | — | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | 
| Earnings per share [text block] | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Earnings per share [abstract] | ||||||||||||||||||
| Earnings per share [line items] | ||||||||||||||||||
| Basic earnings per share [abstract] | ||||||||||||||||||
| Basic earnings (loss) per share from continuing operations | — | — | 
                                                33.00
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                40.00
                                                
                                             | — | — | — | — | — | — | 
| Basic earnings (loss) per share from discontinued operations | — | — | 
                                                25.00
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                40.00
                                                
                                             | — | — | — | — | — | — | 
| Basic earnings (loss) per share | — | — | 
                                                58.00
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                80.00
                                                
                                             | — | — | — | — | — | — | 
| Diluted earnings per share [abstract] | ||||||||||||||||||
| Diluted earnings (loss) per share from continuing operations | — | — | 
                                                33.00
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                40.00
                                                
                                             | — | — | — | — | — | — | 
| Diluted earnings (loss) per share from discontinued operations | — | — | 
                                                25.00
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                40.00
                                                
                                             | — | — | — | — | — | — | 
| Diluted earnings (loss) per share | — | — | 
                                                58.00
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                80.00
                                                
                                             | — | — | — | — | — | — |