Stock Option Plan - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value	$ 0.2	$ 0.0
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, unrecognized compensation cost	$ 0.6
Stock options, cost not yet recognized, remaining weighted average vesting period	11 months 19 days
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized, percentage	1.00%
Shares that remain available for future awards (in shares)	449,332
Maximum employee payroll deduction percentage	20.00%
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	4 years
Stock options, unrecognized compensation cost	$ 5.3
Aggregate intrinsic value, vested	$ 0.4	$ 0.7
Weighted-average grant date fair value (in dollars per share)	$ 2.42	$ 8.61
Stock options, cost not yet recognized, remaining weighted average vesting period	3 years 1 month 6 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 authorized, percentage	4.00%
Shares that remain available for future awards (in shares)	1,746,478

Share-based Compensation Arrangement by Share-based Payment Award, Additional Shares Authorized, Percentage

No definition available.

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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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- Definition

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

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options.

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No definition available.

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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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