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Stock-Based Awards - Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021
Stock-based compensation expense
Stock-based compensation expense	$ 3,692	$ 3,832	$ 6,038	$ 6,507
Unrecognized stock-based compensation expense, options			23,700
Unrecognized stock-based compensation expense, RSUs			18,300
Cost of revenue.
Stock-based compensation expense
Stock-based compensation expense	302	335	530	582
Research and development
Stock-based compensation expense
Stock-based compensation expense	941	1,154	828	2,030
General and administrative
Stock-based compensation expense
Stock-based compensation expense	$ 2,449	$ 2,343	$ 4,680	$ 3,895
Options to purchase common stock
Stock-based compensation expense
Weighted average recognition period unrecognized stock-based compensation cost (in years)			3 years 2 months 12 days
Restricted stock unit awards
Stock-based compensation expense
Weighted average recognition period unrecognized stock-based compensation cost (in years)			3 years