Capital and funding - Summary of Currency Retranslation Reserve (Details) - EUR (€) € in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
|
| Equity and liabilities [abstract] | ||
| Currency retranslation reserve at beginning of period | € (7,026) | € (7,432) |
| Currency retranslation of group companies' net assets and liabilities during the year | (1,522) | (419) |
| Movement in net investment hedges and exchange differences in net investments in foreign operations | (796) | 280 |
| Recycling of currency retranslation to the income statement on demerger of Ice Cream business | 1,036 | 0 |
| Recycling of currency retranslation to the income statement on business disposals | 24 | 545 |
| Currency retranslation reserve at end of period | € (8,284) | € (7,026) |