Provisions - Schedule of maturity of estimated benefits payments, United Kingdom (Details) - United Kingdom € in Millions |
Dec. 31, 2025
EUR (€)
|
|---|---|
| 2026 | |
| Disclosure of net defined benefit liability (asset) [line items] | |
| Estimated future benefit payable | € 576 |
| 2027 | |
| Disclosure of net defined benefit liability (asset) [line items] | |
| Estimated future benefit payable | 485 |
| 2028 | |
| Disclosure of net defined benefit liability (asset) [line items] | |
| Estimated future benefit payable | 503 |
| 2029 | |
| Disclosure of net defined benefit liability (asset) [line items] | |
| Estimated future benefit payable | 527 |
| 2030 | |
| Disclosure of net defined benefit liability (asset) [line items] | |
| Estimated future benefit payable | 545 |
| 2031 to 2035 | |
| Disclosure of net defined benefit liability (asset) [line items] | |
| Estimated future benefit payable | € 2,801 |