Disclosure Of Fair Value Measurement [Text Block]
| Concept | 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 2021-12-31 | As at 2021-12-31 | As at 2021-12-31 | As at 2021-12-31 | As at 2021-12-31 | As at 2021-12-31 | As at 2021-12-31 | As at 2021-12-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Disclosure of fair value measurement [text block] | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| 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 | 
                                                18 500
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | — | — | — | — | — | — | — | 
                                                32 427
                                                
                                                    
                                                        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 | 
                                                5 364
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                2 104
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                3 202
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                218,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                149,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                22,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                2 162
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                403,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                3 587
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                4 511
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                218,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                883,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                386,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                22,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                149,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                924,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                22,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                296,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                3 537
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                930,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                881,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                4 418
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                218,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                149,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
| Reconciliation of changes in fair value measurement, entity's own equity instruments [abstract] |