Equity Plans - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 6,805	$ 3,936	$ 12,740	$ 6,596
Total unrecognized stock-based compensation costs related to stock options	69,000		$ 69,000
Period of unrecognized stock-based compensation costs to be recognized			2 years 8 months 12 days
Research and Development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	4,106	2,155	$ 7,432	3,630
General and Administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 2,699	$ 1,781	$ 5,308	$ 2,966

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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