Commitments and Contingencies (Details) - Jun. 30, 2019 € in Millions, $ in Millions	EUR (€)	USD ($)
Collaborations and Manufacturing Commitments
Potential milestone payable | $		$ 80.0
Manufacturing commitments
Collaborations and Manufacturing Commitments
Manufacturing commitment | $		$ 1.5
Maximum
Collaborations and Manufacturing Commitments
Manufacturing commitment | €	€ 15.1
Minimum
Collaborations and Manufacturing Commitments
Manufacturing commitment | €	€ 2.3