License and Collaboration Agreements - Summary of Revenues (Details) - Gilead and Taiho - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
License
License And Collaboration Agreements [Line Items]
Total revenues		$ 55,096		$ 55,096
Collaboration
License And Collaboration Agreements [Line Items]
Total revenues	$ 9,461	9,434	$ 28,383	12,934
Collaboration and License
License And Collaboration Agreements [Line Items]
Total revenues	$ 9,461	$ 64,530	$ 28,383	$ 68,030