Nature of Operations (Details) $ in Millions		3 Months Ended
Mar. 15, 2019	Mar. 31, 2021 USD ($) ClinicalTrial
Nature of Operations [Abstract]
Reverse stock split ratio	0.05
Number of planned clinical trials delayed		2
Number of planned clinical trials		3
Ministry of Science, Technology and Innovation of Brazil [Member] \| Clinical Development and Commercialization of COVID-19 Vaccine [Member]
Nature of Operations [Abstract]
Committed funding to COVID-19 vaccine consortium \| $		$ 60

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187143-122770

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