v3.26.1
Note 6 Maximum credit risk exposure (Details) - EUR (€)
€ in Millions
Jun. 30, 2026
Dec. 31, 2025
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk € 1,260,354 € 1,104,820
Financial assets held for trading [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 115,888 90,634
Financial assets held for trading [Member] | equity instruments [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 12,181 9,901
Financial assets held for trading [Member] | Debt securities [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 36,343 30,846
Financial assets held for trading [Member] | loans and advances [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 67,363 49,887
Non trading financial assets mandatorily at fair value through profit or loss [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 13,171 11,272
Non trading financial assets mandatorily at fair value through profit or loss [Member] | equity instruments [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 12,253 10,539
Non trading financial assets mandatorily at fair value through profit or loss [Member] | Debt securities [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 146 192
Non trading financial assets mandatorily at fair value through profit or loss [Member] | loans and advances [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 772 541
Financial assets designated at fair value through profit or loss [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 1,007 1,006
Derivatives [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 55,466 49,141
Financial assets at fair value through other comprehensive income, category [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 62,313 58,919
Financial assets at fair value through other comprehensive income, category [member] | equity instruments [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 790 1,360
Financial assets at fair value through other comprehensive income, category [member] | Debt securities [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 60,709 57,046
Financial assets at fair value through other comprehensive income, category [member] | Loans and advances to credit institutions [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 814 513
Financial assets at amortised cost, category [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 640,815 581,271
Financial assets at amortised cost, category [member] | Debt securities [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 73,750 73,429
Financial assets at amortised cost, category [member] | Loans and advances to credit institutions [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 32,419 24,263
Financial assets at amortised cost, category [member] | Loans and advances to central banks [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 12,102 10,881
Financial assets at amortised cost, category [member] | Loans and advances to customers [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 522,544 472,697
Total financial assets risk [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 888,660 792,242
Total loan commitments and financial guarantees [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 371,693 312,578
Total loan commitments and financial guarantees [Member] | Loan commitments [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 267,238 227,554
Total loan commitments and financial guarantees [Member] | Financial guarantee contracts [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 26,861 24,865
Total loan commitments and financial guarantees [Member] | Other commitments given [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 77,595 60,159
Stage 1 [Member] | Financial assets at fair value through other comprehensive income, category [member] | Debt securities [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 60,709 57,020
Stage 1 [Member] | Financial assets at fair value through other comprehensive income, category [member] | Loans and advances to credit institutions [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 282 24
Stage 1 [Member] | Financial assets at amortised cost, category [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 591,745 536,123
Stage 1 [Member] | Financial assets at amortised cost, category [member] | Debt securities [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 73,705 73,387
Stage 1 [Member] | Financial assets at amortised cost, category [member] | Loans and advances to credit institutions [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 32,419 24,230
Stage 1 [Member] | Financial assets at amortised cost, category [member] | Loans and advances to central banks [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 12,102 10,881
Stage 1 [Member] | Financial assets at amortised cost, category [member] | Loans and advances to customers [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 473,519 427,625
Stage 1 [Member] | Total loan commitments and financial guarantees [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 360,871 303,063
Stage 1 [Member] | Total loan commitments and financial guarantees [Member] | Loan commitments [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 259,595 220,990
Stage 1 [Member] | Total loan commitments and financial guarantees [Member] | Financial guarantee contracts [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 26,170 23,988
Stage 1 [Member] | Total loan commitments and financial guarantees [Member] | Other commitments given [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 75,106 58,084
Stage 2 [Member] | Financial assets at fair value through other comprehensive income, category [member] | Debt securities [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 0 0
Stage 2 [Member] | Financial assets at fair value through other comprehensive income, category [member] | Loans and advances to credit institutions [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 532 488
Stage 2 [Member] | Financial assets at amortised cost, category [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 33,586 30,765
Stage 2 [Member] | Financial assets at amortised cost, category [member] | Debt securities [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 6 5
Stage 2 [Member] | Financial assets at amortised cost, category [member] | Loans and advances to credit institutions [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 0 34
Stage 2 [Member] | Financial assets at amortised cost, category [member] | Loans and advances to central banks [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 0 0
Stage 2 [Member] | Financial assets at amortised cost, category [member] | Loans and advances to customers [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 33,580 30,727
Stage 2 [Member] | Total loan commitments and financial guarantees [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 10,173 8,839
Stage 2 [Member] | Total loan commitments and financial guarantees [Member] | Loan commitments [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 7,451 6,385
Stage 2 [Member] | Total loan commitments and financial guarantees [Member] | Financial guarantee contracts [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 569 739
Stage 2 [Member] | Total loan commitments and financial guarantees [Member] | Other commitments given [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 2,152 1,715
Stage 3 [Member] | Financial assets at fair value through other comprehensive income, category [member] | Debt securities [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 0 25
Stage 3 [Member] | Financial assets at fair value through other comprehensive income, category [member] | Loans and advances to credit institutions [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 0 0
Stage 3 [Member] | Financial assets at amortised cost, category [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 15,483 14,383
Stage 3 [Member] | Financial assets at amortised cost, category [member] | Debt securities [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 39 37
Stage 3 [Member] | Financial assets at amortised cost, category [member] | Loans and advances to credit institutions [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 0 0
Stage 3 [Member] | Financial assets at amortised cost, category [member] | Loans and advances to central banks [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 0 0
Stage 3 [Member] | Financial assets at amortised cost, category [member] | Loans and advances to customers [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 15,444 14,346
Stage 3 [Member] | Total loan commitments and financial guarantees [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 649 676
Stage 3 [Member] | Total loan commitments and financial guarantees [Member] | Loan commitments [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 191 179
Stage 3 [Member] | Total loan commitments and financial guarantees [Member] | Financial guarantee contracts [member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk 121 138
Stage 3 [Member] | Total loan commitments and financial guarantees [Member] | Other commitments given [Member]    
Credit Exposure Classes of Financial Instruments [Line Items]    
Maximum exposure to credit risk € 337 € 359