Collaboration Agreements (Details) - GBG Forschungs GmbH € in Millions	1 Months Ended		6 Months Ended
	Apr. 30, 2020 EUR (€)	Sep. 30, 2019 patient	Jun. 30, 2020 EUR (€)
Restructuring Cost and Reserve [Line Items]
Number of patients in clinical collaboration (in patients) | patient		1,200
Potential milestone payment			€ 33.0
Potential milestone payment terms (in years)			6 years
Accrued expenses			€ 0.5
Milestone Payment	€ 3.0