Financial liabilities - Disclosure of changes in derivative instruments (Details) - EUR (€) € in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 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	175
Decrease in fair value	0	(145)
Repurchases	0
Exercises	0
Derivative financial liabilities at end of period	0	4,816
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	0	0
Decrease in fair value	0	(145)
Repurchases	0
Exercises	0
Derivative financial liabilities at end of period	0	1,021
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	0	175
Decrease in fair value	0	0
Repurchases	0
Exercises	0
Derivative financial liabilities at end of period	€ 0	€ 3,795

Exercise Of Derivative Instruments

No definition available.

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- Definition

Repurchase Of Derivative Instruments

+ References

No definition available.

+ Details

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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
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_55&doctype=Standard
-URIDate 2025-03-27

+ Details

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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.

+ Details

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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

+ Details

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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

+ Details

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- Details

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