v3.26.1
Taxation (Details) - EUR (€)
€ in Millions
12 Months Ended
Dec. 31, 2032
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
[1]
Taxation        
Tax effect from change in tax rate   € (51)    
Income tax expense   € (115) € (231) € (43)
Spain        
Taxation        
Tax rate (as a percent)   25.00%    
US        
Taxation        
Tax rate (as a percent)   22.00%    
Germany        
Taxation        
Statutory corporate income tax rate   15.00%    
Solidarity surcharge rate on statutory corporate income tax rate   5.50%    
Statutory corporate income tax rate including solidarity surcharge   15.825%    
Tax effect from change in tax rate   € (51)    
Germany | Forecast        
Taxation        
Statutory corporate income tax rate 10.00%      
Germany | Minimum        
Taxation        
Tax rate (as a percent)   23.00%    
Germany | Maximum        
Taxation        
Tax rate (as a percent)   33.00%    
[1] (See Note 2.d)