Balance Sheet Details - Summary of Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Accrued interest expense on deferred royalty obligation, current portion	$ 4,726	$ 3,567
Deferred revenue	2,976	188
Accrued royalties and in-license fees	1,283	685
Accrued manufacturing costs	1,230	627
Accrued professional fees	436	660
Accrued other	1,069	767
Total accrued expenses	$ 11,720	$ 6,494