Revenue - Collaboration revenue (Details) - EUR (€) € in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Disclosure of disaggregation of revenue from contracts with customers [line items]
Collaboration revenue	€ 655	€ 1,130
Eli Lilly and Company
Disclosure of disaggregation of revenue from contracts with customers [line items]
Collaboration revenue	€ 655	804
Yarrow Biotechnology, Inc
Disclosure of disaggregation of revenue from contracts with customers [line items]
Collaboration revenue		€ 326

The amount of revenue from contracts with customers. A customer is a party that has contracted with an entity to obtain goods or services that are an output of the entity’s ordinary activities in exchange for consideration.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2022-03-24
-Paragraph 114
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2022-en-r&anchor=para_114&doctype=Standard
-URIDate 2022-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2022-03-24
-Paragraph 113
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2022-en-r&anchor=para_113_a&doctype=Standard
-URIDate 2022-03-24

Name:	ifrs-full_RevenueFromContractsWithCustomers
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration