Disclosure Of Non-Current Assets Held For Sale And Discontinued Operations [Text Block]
| Concept | 2024-01-01 to 2024-12-31 | 2023-01-01 to 2023-12-31 | 2022-01-01 to 2022-12-31 | 
|---|---|---|---|
| Disclosure of non-current assets held for sale and discontinued operations [text block] | — | — | — | 
| Disclosure of analysis of single amount of discontinued operations [text block] | — | — | — | 
| Disclosure of analysis of single amount of discontinued operations [abstract] | |||
| Disclosure of analysis of single amount of discontinued operations [line items] | |||
| Profit (loss) before tax | 
                                                123,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                526,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1,731,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
| Revenue | 
                                                18,021,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                18,169,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                17,827,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
| Profit (loss) from discontinued operations | 
                                                142,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                10,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                13,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
| Cash flows from continuing and discontinued operations [abstract] | |||
| Cash flows from (used in) operating activities [abstract] | |||
| Cash flows from (used in) operating activities, continuing operations | 
                                                1,569,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                2,136,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                173,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
| Cash flows from (used in) investing activities [abstract] | |||
| Cash flows from (used in) investing activities, continuing operations | 
                                                573,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                636,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                1,487,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
| Cash flows from (used in) financing activities [abstract] | |||
| Cash flows from (used in) financing activities, continuing operations | 
                                                496,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                848,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                500,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
| Increase (decrease) in cash and cash equivalents, discontinued operations | 
                                                13,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                123,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             | 
                                                12,000,000
                                                
                                                    
                                                        EUR
                                                    
                                                
                                             |