Operating expenses - Summary of Research and Development Expenses (Details) - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Analysis of income and expense [abstract]
Purchases, sub-contracting and other expenses	€ (19,562)	€ (12,734)	€ (16,804)
Payroll costs (including share-based payments)	(9,605)	(10,306)	(11,980)
Depreciation, amortization, and provision expenses	(1,211)	(1,290)	(1,627)
Research and development expenses	€ (30,378)	€ (24,330)	€ (30,411)

The amount of expenditure directly attributable to research or development activities, recognised in profit or loss.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 38
-IssueDate 2021-01-01
-Paragraph 126
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=38&code=ifrs-tx-2021-en-r&anchor=para_126&doctype=Standard
-URIDate 2021-03-24

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration