Shareholders equity - Share options (Details) - EUR (€)	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Operating costs
Shareholders Equity
Compensation expenses	€ 1,921,000	€ 2,719,000
General and administrative costs
Shareholders Equity
Compensation expenses	1,537,000	1,673,000
Research and development costs
Shareholders Equity
Compensation expenses	€ 384,000	€ 1,046,000

The amount of expense arising from share-based payment transactions in which the goods or services received did not qualify for recognition as assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2021-01-01
-Paragraph 51
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_51_a&doctype=Standard
-URIDate 2021-03-24

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