Stock-based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Stock-based compensation
Proceeds from issuances of common stock from employee stock purchase plans	$ 203	$ 358
Unrecognized compensation cost related to outstanding options	$ 47,103
Period over which unrecognized compensation cost is expected to be recognized as expense	2 years 9 months 18 days
Stock-based compensation expense	$ 6,135	6,879
Restricted stock units
Stock-based compensation
Vesting period (in years)	4 years
Total fair value of shares vested	$ 8,001	$ 9,116
Stock options
Stock-based compensation
Weighted-average grant date fair value per share of grants (in dollars per share)	$ 0	$ 12.08
Employee stock purchase plan
Stock-based compensation
Employee Stock Purchase Plan, Purchase Price Percentage	85.00%
Issuance for employee stock purchase plan, shares	13,421
Proceeds from issuances of common stock from employee stock purchase plans	$ 203
Total purchased proceeds	$ 32	$ 72

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Employee Stock Purchase Plan, Purchase Price Percentage

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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.

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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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Amount of noncash expense for share-based payment arrangement.

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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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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

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