Provisions - Schedule of funding status of the defined benefit obligations, United Kingdom (Details) - United Kingdom - EUR (€) € in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
|---|---|---|---|
| Disclosure of net defined benefit liability (asset) [line items] | |||
| Present value of the obligations | € 8,164 | € 8,898 | € 9,451 |
| Fair value of plan assets | 8,740 | 9,400 | 10,208 |
| Provisions - Provisions for pensions | (576) | (502) | (757) |
| Internal provisions for pensions | 25 | 28 | 76 |
| Net assets for pensions | € (601) | € (530) | € (833) |