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Stock Option Plan - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 1,440	$ 1,285	$ 2,816	$ 2,197
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, unrecognized compensation cost	$ 4,200		$ 4,200
Stock options, cost not yet recognized, remaining weighted average vesting period			1 year 7 months 6 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		453,484
Maximum employee payroll deduction percentage	20.00%		20.00%
Stock options, cost not yet recognized, remaining weighted average vesting period			2 months 12 days
Stock-based compensation expense	$ 100	$ 100	$ 100	$ 100
Unrecognized compensation cost related to stock purchase	100		100
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, unrecognized compensation cost	$ 8,200		$ 8,200
Stock options, cost not yet recognized, remaining weighted average vesting period			3 years 3 months 18 days
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)	1,430,690		1,430,690