Related party disclosures - Additional Information (Detail) € in Millions	6 Months Ended
Jun. 30, 2026 EUR (€) shares
Disclosure of transactions between related parties [line items]
Key management personnel compensation, termination benefits \| €	€ 0.3
Service Options To Its Board [Member]
Disclosure of transactions between related parties [line items]
Number of share options granted in share-based payment arrangement	384,000
Service Options To Purchase Ordinary Shares [Member]
Disclosure of transactions between related parties [line items]
Number of share options granted in share-based payment arrangement	1,993,750
Key management personnel of entity or parent [member] \| Restricted Stock Units [Member]
Disclosure of transactions between related parties [line items]
Number of share options granted in share-based payment arrangement	477,500

The number of share options granted in a share-based payment arrangement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 45
-Subparagraph b
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2025-en-r&anchor=para_45_b_ii&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 31
-Subparagraph b
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_31_b_ii&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 31
-Subparagraph b
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_31_b_ii&doctype=Standard
-URIDate 2025-03-27

Name:	ifrs-full_NumberOfShareOptionsGrantedInSharebasedPaymentArrangement
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration