Disclosure Of Effect Of Changes In Foreign Exchange Rates [Text Block]
| Concept | 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 | 2023-01-01 to 2023-12-31 | As at 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 2022-01-01 to 2022-12-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Disclosure of effect of changes in foreign exchange rates [text block] | — | — | — | — | — | — | — | — | — | — | — | — | 
| Disclosure of information when currency is not exchangeable into another currency [text block] | — | — | — | — | — | — | — | — | — | — | — | — | 
| Disclosure of information when foreign operation’s functional currency is not exchangeable into presentation currency [text block] | — | — | — | — | — | — | — | — | — | — | — | — | 
| Disclosure of summarised financial information about foreign operation [text block] | — | — | — | — | — | — | — | — | — | — | — | — | 
| Disclosure of summarised financial information about foreign operation [abstract] | ||||||||||||
| Disclosure of summarised financial information about foreign operation [line items] | ||||||||||||
| Non-current assets | — | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | 
                                                23 485
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | 
| Current assets | — | 
                                                18 500
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | 
                                                8 942
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | 
| Non-current liabilities | — | 
                                                -
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | 
                                                16 132
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | 
| Current liabilities | — | 
                                                23 864
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | 
                                                12 708
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | 
| Revenue | 
                                                17,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | 
                                                17,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | 
| Profit (loss) from continuing operations | 
                                                536,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | 
                                                10,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | 
| Profit (loss) from discontinued operations | 
                                                8 028
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | 
                                                423,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | 
| Profit (loss) | 
                                                8 564
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | 
                                                6 621
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1 943
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1 943
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | 
                                                141,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                413,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | 
                                                141,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                272,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
| Other comprehensive income | 
                                                540,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | 
                                                398,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | 
                                                142,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                142,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | 
                                                23,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                208,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                23,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | 
                                                185,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
| Comprehensive income | 
                                                8 024
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | 
                                                6 223
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1 943
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1 801
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                142,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | 
                                                118,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                205,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                23,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                141,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                87,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             |