Collaboration Agreements - Other Revenue (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Collaboration agreements
Collaboration revenue	$ 11,000	$ 11,000	$ 32,000	$ 817,000
Asana BioSciences
Collaboration agreements
Next potential milestone payment eligible to receive	$ 2,500,000		2,500,000
Asana BioSciences | Limited services
Collaboration agreements
Collaboration revenue			$ 0	$ 0