Commitments and Contingencies - Additional Information (Details) $ in Millions	Mar. 31, 2021 USD ($)
Product Liability Contingency [Line Items]
Other Commitment, Due in Next Twelve Months	$ 1.7
Drug Supplier Project Plan [Member]
Product Liability Contingency [Line Items]
Other Commitment	2.6
Manufacture of Prexigebersen [Member]
Product Liability Contingency [Line Items]
Other Commitment	1.3
Manufacture of Drug Substance [Member]
Product Liability Contingency [Line Items]
Other Commitment	1.1
Manufacturing Development [Member]
Product Liability Contingency [Line Items]
Other Commitment	0.1
Testing Services [Member]
Product Liability Contingency [Line Items]
Other Commitment	$ 0.1