Fair value of financial assets and liabilities - Financial liabilities subject to offsetting, enforceable master netting arrangements or similar agreements (Detail) - Derivatives - EUR (€) € in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Fair value of financial assets and liabilities [Line Items] | ||
| Gross financial liabilities subject to offsetting, enforceable master netting arrangements or similar agreements | € (39) | € (63) |
| Net financial liabilities subject to offsetting, enforceable master netting arrangements or similar agreements in statement of financial position | (39) | (63) |
| Financial instruments | 32 | 45 |
| Net amount | € (7) | € (18) |