Revenue - Schedule of Collaboration Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation Of Revenue [Line Items]
Revenue	$ 2,218	$ 13,384	$ 6,576	$ 20,462
Collaboration Revenue [Member]
Disaggregation Of Revenue [Line Items]
Revenue	2,218	13,384	3,576	20,462
Neurocrine Biosciences [Member] | Collaboration Revenue [Member]
Disaggregation Of Revenue [Line Items]
Recognition of the transaction price	617	11,916	617	17,760
Research and development services	$ 1,601	$ 1,468	2,959	$ 2,702
Flexion [Member] | Collaboration Revenue [Member]
Disaggregation Of Revenue [Line Items]
Milestone payments			$ 3,000