Equity Incentive Plan - Unrecognized compensation (Details) - 2019 Plan $ in Millions	6 Months Ended
Jun. 30, 2022 USD ($)
Common stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 21.1
Remaining weighted-average requisite service period	2 years 1 month 6 days
Unvested restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 2.8
Remaining weighted-average requisite service period	1 year 2 months 12 days

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of cost to be recognized for option under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Topic 718
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+ References

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