Balance Sheet Details - Details of Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Accrued clinical trial expenses	$ 14,774	$ 16,477
Accrued compensation	9,023	10,917
Accrued milestone payment	4,500	15,000
Other accrued liabilities	14,477	12,570
Total	$ 42,774	$ 54,964

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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