Events after the end of the reporting period (Details) - Global exclusive license agreement with Novartis [member] € in Millions	Jul. 19, 2018 EUR (€)
Disclosure of non-adjusting events after reporting period [line items]
Future upfront payments	€ 95
Potential future milestone payments	€ 850

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

No definition available.

Name:	ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration