Share-based compensation - Narrative (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Performance Share Units and Restricted Share Units
Disclosure of terms and conditions of share-based payment arrangement [line items]
Expense from share-based payment transactions with employees	€ 73	€ 45	€ 189

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration