Basis of preparation and significant changes in the current reporting period - Reconciliation net result under IFRS-EU and IFRS-IASB (Details) - EUR (€) € in Millions |
6 Months Ended | 12 Months Ended | |
|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Dec. 31, 2024 |
|
| Disclosure of Reconciliation Net Result EU IFRS and IASB IFRS [Abstract] | |||
| In accordance with IFRS-EU (attributable to the shareholders of the parent) | € 3,130 | € 3,358 | |
| Adjustment of the EU IAS 39 carve-out | 1,065 | 1,512 | |
| Tax effect of the adjustment | (279) | (414) | |
| Effect of adjustment after tax | 786 | 1,099 | € 1,099 |
| Shareholders of the parent | € 3,915 | € 4,456 | |