Financial liabilities - Disclosure of changes in derivative instruments (Details) - EUR (€) € in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disclosure of detailed information about financial instruments [line items]
Derivative financial liabilities at beginning of period			€ 0	€ 4,786
Increase in fair value	€ 0	€ 536	0	482
Decrease in fair value	0	(156)	0	(72)
Derivative financial liabilities at end of period	0	5,196	0	5,196
Kreos/Claret BSA
Disclosure of detailed information about financial instruments [line items]
Derivative financial liabilities at beginning of period			0	1,166
Increase in fair value				391
Decrease in fair value				0
Derivative financial liabilities at end of period	0	1,557	0	1,557
Kreos/Claret Minimal Return Indemnifications
Disclosure of detailed information about financial instruments [line items]
Derivative financial liabilities at beginning of period			0	3,620
Increase in fair value				91
Decrease in fair value				(72)
Derivative financial liabilities at end of period	€ 0	€ 3,639	€ 0	€ 3,639

The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
-IssueDate 2025-01-01
-Paragraph 55
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-URIDate 2025-03-27

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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.

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No definition available.

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- Definition

The gains resulting from change in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
-IssueDate 2025-01-01
-Paragraph 85
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_85&doctype=Standard
-URIDate 2025-03-27

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The losses resulting from changes in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]]

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