v3.26.1
Intangible assets - Schedule of changes in intangible assets (Details) - EUR (€)
€ in Millions
 6 Months Ended 12 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January € 1,510 € 1,334 € 1,334
Additions 89 35  
Capitalised expenses 174 380  
Amortisation (114) (223)  
Impairment (3) (7)  
Exchange rate differences 16 (9)  
Disposals (2)  
Other changes 69 2  
Closing balance 1,740   1,510
Gross carrying amount      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January 3,767    
Closing balance 4,097   3,767
Accumulated amortisation      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January (2,201)    
Closing balance (2,300)   (2,201)
Accumulated impairments      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January (55)    
Closing balance (57)   (55)
Goodwill      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January 477 476 476
Additions 71  
Impairment  
Exchange rate differences (2) 1  
Other changes 43  
Closing balance 588   477
Goodwill | Gross carrying amount      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January 477    
Closing balance 588   477
Goodwill | Accumulated impairments      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January    
Closing balance  
Software      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January 1,030 855 855
Additions 18 35  
Capitalised expenses 174 380  
Amortisation (113) (223)  
Impairment (3) (7)  
Exchange rate differences 18 (10)  
Disposals (2)  
Other changes 2  
Closing balance 1,124   1,030
Software | Gross carrying amount      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January 3,281    
Closing balance 3,474   3,281
Software | Accumulated amortisation      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January (2,197)    
Closing balance (2,295)   (2,197)
Software | Accumulated impairments      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January (53)    
Closing balance (56)   (53)
Other      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January 3 3 3
Additions  
Capitalised expenses  
Amortisation (1)  
Impairment  
Exchange rate differences 0  
Disposals  
Other changes 26 € 1  
Closing balance 28   3
Other | Gross carrying amount      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January 9    
Closing balance 35   9
Other | Accumulated amortisation      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January (4)    
Closing balance (5)   (4)
Other | Accumulated impairments      
Disclosure of detailed information about intangible assets [line items]      
Opening balance as at 1 January (1)    
Closing balance € (1)   € (1)