Revenue - Summary of Deferred Revenue Activity (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2020 USD ($)
Movement in Deferred Revenue [Roll Forward]
Balance at beginning of period	$ 918
Additions to deferred revenue	0
Recognized as revenue	(101)
Balance at end of period	817
NIDA Grant
Movement in Deferred Revenue [Roll Forward]
Balance at beginning of period	918
Additions to deferred revenue	0
Recognized as revenue	(101)
Balance at end of period	$ 817