v3.25.4
Note 10 Derivatives by type of risk and by product or by type of market (Details) - EUR (€)
€ in Millions
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading € 32,551 € 36,003 € 34,293
Derivative financial liabilities held for trading 30,345 33,059 33,045
Interest rate risk [member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 13,040 11,588 15,251
Derivative financial liabilities held for trading 9,573 9,627 13,171
Notional amount 4,948,476 4,951,022 4,741,629
Interest rate risk [member] | OTC Options [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 13,034 11,579 15,248
Derivative financial liabilities held for trading 9,536 9,622 13,167
Notional amount 4,923,960 4,930,657 4,722,314
Interest rate risk [member] | Organized market options [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 6 10 3
Derivative financial liabilities held for trading 36 4 4
Notional amount 24,516 20,365 19,315
Equity risk [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 3,447 2,944 2,587
Derivative financial liabilities held for trading 5,439 4,303 3,723
Notional amount 94,665 75,045 70,804
Equity risk [Member] | OTC Options [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 997 682 1,212
Derivative financial liabilities held for trading 3,724 2,347 2,551
Notional amount 41,328 38,612 49,038
Equity risk [Member] | Organized market options [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 2,450 2,261 1,375
Derivative financial liabilities held for trading 1,714 1,956 1,172
Notional amount 53,337 36,433 21,767
Foreign exchange and gold risk [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 15,150 21,060 15,911
Derivative financial liabilities held for trading 14,507 18,704 15,608
Notional amount 1,012,015 825,158 632,780
Foreign exchange and gold risk [Member] | OTC Options [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 15,041 21,056 15,889
Derivative financial liabilities held for trading 14,441 18,698 15,590
Notional amount 997,308 810,770 623,203
Foreign exchange and gold risk [Member] | Organized market options [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 109 4 22
Derivative financial liabilities held for trading 66 7 18
Notional amount 14,707 14,388 9,577
Credit risk [member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 790 386 543
Derivative financial liabilities held for trading 756 375 542
Notional amount 66,427 42,799 31,478
Credit risk [member] | Credit default swap contract [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 681 349 540
Derivative financial liabilities held for trading 720 369 528
Notional amount 62,702 40,847 29,844
Credit risk [member] | Credit spread option contract [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 0 0 0
Derivative financial liabilities held for trading 0 0 0
Notional amount 0 0 0
Credit risk [member] | Total return swap contract [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 109 37 3
Derivative financial liabilities held for trading 36 0 14
Notional amount 3,725 1,952 1,475
Credit risk [member] | Other [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 0 0 0
Derivative financial liabilities held for trading 0 6 0
Notional amount 0 0 159
Commodity price risk [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 124 25 1
Derivative financial liabilities held for trading 70 50 1
Notional amount 4,521 1,939 169
Derivatives [member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 32,551 36,003 34,293
Derivative financial liabilities held for trading 30,345 33,059 33,045
Notional amount 6,126,104 5,895,964 5,476,860
Derivatives [member] | Of which OTC credit institutions [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 19,738 26,039 23,998
Derivative financial liabilities held for trading 19,538 23,135 23,977
Notional amount 1,840,752 1,742,720 1,463,433
Derivatives [member] | Of which OTC other financial corporations [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 6,387 3,383 5,042
Derivative financial liabilities held for trading 5,336 4,212 4,412
Notional amount 4,004,652 3,914,640 3,815,162
Derivatives [member] | Of which OTC other [Member]      
Derivatives by type of risk by product or by type of market [Line Items]      
Derivative financial assets held for trading 3,862 4,306 3,854
Derivative financial liabilities held for trading 3,655 3,744 3,461
Notional amount € 185,799 € 166,402 € 147,310