Financial liabilities - Disclosure of changes in derivative instruments (Details) - EUR (€) € in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Disclosure of detailed information about financial instruments [line items]
Derivative financial liabilities at beginning of period			€ 4,786	€ 2,579
Issuance				2,158
Increase in fair value	€ 536	€ 639	482	1,547
Decrease in fair value	(156)	(306)	(72)	(27)
Derivative financial liabilities at end of period	5,196	6,257	5,196	6,257
Kreos/Claret BSA
Disclosure of detailed information about financial instruments [line items]
Derivative financial liabilities at beginning of period			1,166	2,579
Issuance				0
Increase in fair value			391	1,542
Decrease in fair value			0	0
Derivative financial liabilities at end of period	1,557	4,121	1,557	4,121
Kreos/Claret Minimum Return Indemnifications
Disclosure of detailed information about financial instruments [line items]
Derivative financial liabilities at beginning of period			3,620	0
Issuance				2,158
Increase in fair value			91	5
Decrease in fair value			(72)	(27)
Derivative financial liabilities at end of period	€ 3,639	€ 2,136	€ 3,639	€ 2,136

Issuance Of Derivative Instruments

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- Definition

The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; 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
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- Definition

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.

+ References

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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- Definition

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

+ References

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