Subsequent Events - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended
	Mar. 31, 2020	Oct. 31, 2017	Feb. 29, 2020
Human Immunodeficiency Virus (“HIV”) Grant | Subsequent Event
Subsequent Event [Line Items]
Grant awarded amount			$ 8.6
Alnylam Agreement | Alnylam
Subsequent Event [Line Items]
Issuance of common stock, shares		1,111,111
Alnylam Agreement | Scenario Forecast | Alnylam
Subsequent Event [Line Items]
Obligation payment	$ 15.0
Milestone payment period	30 days
Issuance of common stock, shares	1,111,111
Milestone payment shares issuance period	60 days
Maximum milestone payment for achievement of specified development	$ 15.0