Stock-based Compensation - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Stock-based compensation
Proceeds from issuances of common stock from employee stock purchase plan	$ 169	$ 203
Unrecognized compensation cost related to outstanding options	$ 61,072
Period over which unrecognized compensation cost is expected to be recognized as expense	2 years 10 months 24 days
Restricted stock units
Stock-based compensation
Vesting period (in years)	4 years
Total fair value of shares vested	$ 14,779	8,001
Employee stock purchase plan.
Stock-based compensation
Employee Stock Purchase Plan, Purchase Price Percentage	85.00%
Issuance for employee stock purchase plan, shares	11,329
Proceeds from issuances of common stock from employee stock purchase plan	$ 169
Employee stock purchase plan compensation expenses	$ 46	$ 32

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Employee Stock Purchase Plan, Purchase Price Percentage

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+ References

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Amount of cost to be recognized for option under share-based payment arrangement.

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Amount of cash inflow from issuance of shares under share-based payment arrangement. Excludes option exercised.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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