Gains and losses on derecognition of financial assets measured at amortized cost (Detail: Text Values) - EUR (€) € in Millions	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Gain and Losses on derecognition of Financial Assets at Amortized Cost [Abstract]
Total financial assets measured at amortized cost sold	€ 360	€ 173

The decrease in financial assets resulting from derecognition. [Refer: Financial assets]

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