Trade receivables - Narrative (Details) - EUR (€) € in Millions	6 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Trade and other receivables [abstract]
Trade receivables past due	€ 1.5	€ 1.5
Receivables from contracts with customers	16.3	€ 27.8
Decrease in trade receivables	€ 11.5

The amount of an entity’s right to consideration in exchange for goods or services that the entity has transferred to a customer that is unconditional. A right to consideration is unconditional if only the passage of time is required before payment of that consideration is due.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2025-01-01
-Paragraph 105
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2025-en-r&anchor=para_105&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2025-01-01
-Paragraph 116
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2025-en-r&anchor=para_116_a&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 105
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_105_a&doctype=Standard
-URIDate 2025-03-27

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 105
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_105_a&doctype=Standard
-URIDate 2025-03-27

Name:	ifrs-full_ReceivablesFromContractsWithCustomers
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant