v3.25.4
Risk management - Foreign currency exposures banking books (Details) - EUR (€)
€ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Trading income (expense) [line items]    
Net banking currency exposures banking books € 15,565 € 15,834
Foreign Investments    
Trading income (expense) [line items]    
Net banking currency exposures banking books 27,573 29,509
Hedges    
Trading income (expense) [line items]    
Net banking currency exposures banking books (12,008) (13,675)
US Dollar    
Trading income (expense) [line items]    
Net banking currency exposures banking books 5,198 6,429
US Dollar | Foreign Investments    
Trading income (expense) [line items]    
Net banking currency exposures banking books 9,698 11,251
US Dollar | Hedges    
Trading income (expense) [line items]    
Net banking currency exposures banking books (4,500) (4,823)
British Pound    
Trading income (expense) [line items]    
Net banking currency exposures banking books 1,069 1,190
British Pound | Foreign Investments    
Trading income (expense) [line items]    
Net banking currency exposures banking books 1,584 1,674
British Pound | Hedges    
Trading income (expense) [line items]    
Net banking currency exposures banking books (515) (484)
Polish Zloty    
Trading income (expense) [line items]    
Net banking currency exposures banking books 2,643 2,677
Polish Zloty | Foreign Investments    
Trading income (expense) [line items]    
Net banking currency exposures banking books 4,652 4,292
Polish Zloty | Hedges    
Trading income (expense) [line items]    
Net banking currency exposures banking books (2,009) (1,616)
Australian Dollar    
Trading income (expense) [line items]    
Net banking currency exposures banking books 1,374 1,212
Australian Dollar | Foreign Investments    
Trading income (expense) [line items]    
Net banking currency exposures banking books 3,307 3,373
Australian Dollar | Hedges    
Trading income (expense) [line items]    
Net banking currency exposures banking books (1,933) (2,161)
Turkish Lira    
Trading income (expense) [line items]    
Net banking currency exposures banking books 469 557
Turkish Lira | Foreign Investments    
Trading income (expense) [line items]    
Net banking currency exposures banking books 469 557
Turkish Lira | Hedges    
Trading income (expense) [line items]    
Net banking currency exposures banking books 0 0
Chinese Yuan    
Trading income (expense) [line items]    
Net banking currency exposures banking books 2,016 1,609
Chinese Yuan | Foreign Investments    
Trading income (expense) [line items]    
Net banking currency exposures banking books 2,015 2,439
Chinese Yuan | Hedges    
Trading income (expense) [line items]    
Net banking currency exposures banking books 1 (830)
Russian Rouble    
Trading income (expense) [line items]    
Net banking currency exposures banking books 597 396
Russian Rouble | Foreign Investments    
Trading income (expense) [line items]    
Net banking currency exposures banking books 597 396
Russian Rouble | Hedges    
Trading income (expense) [line items]    
Net banking currency exposures banking books 0 0
Romanian Leu    
Trading income (expense) [line items]    
Net banking currency exposures banking books 685 736
Romanian Leu | Foreign Investments    
Trading income (expense) [line items]    
Net banking currency exposures banking books 913 913
Romanian Leu | Hedges    
Trading income (expense) [line items]    
Net banking currency exposures banking books (228) (176)
Thai Baht    
Trading income (expense) [line items]    
Net banking currency exposures banking books 478 428
Thai Baht | Foreign Investments    
Trading income (expense) [line items]    
Net banking currency exposures banking books 1,307 1,266
Thai Baht | Hedges    
Trading income (expense) [line items]    
Net banking currency exposures banking books (829) (838)
Other currency    
Trading income (expense) [line items]    
Net banking currency exposures banking books 1,036 599
Other currency | Foreign Investments    
Trading income (expense) [line items]    
Net banking currency exposures banking books 3,032 3,346
Other currency | Hedges    
Trading income (expense) [line items]    
Net banking currency exposures banking books € (1,995) € (2,748)