Stock Option Plan - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	0
Stock-based compensation expense	$ 1,376	$ 912
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, unrecognized compensation cost	$ 5,400
Stock options, cost not yet recognized, remaining weighted average vesting period	1 year 8 months 12 days
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares that remain available for future awards (in shares)	453,484
Maximum employee payroll deduction percentage	20.00%
Stock options, cost not yet recognized, remaining weighted average vesting period	4 months 24 days
Stock-based compensation expense	$ 100	$ 100
Unrecognized compensation cost related to stock purchase	100
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, unrecognized compensation cost	$ 9,400
Stock options, cost not yet recognized, remaining weighted average vesting period	3 years 6 months
2019 Incentive Award Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, expiration period	10 years
Stock options, vesting period	4 years
Shares that remain available for future awards (in shares)	1,328,586

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

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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Gross number of share options (or share units) granted during the period.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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