Stock Option Plan - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value		$ 0.2
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, unrecognized compensation cost	$ 0.1
Stock options, cost not yet recognized, remaining weighted average vesting period	2 years 2 months 23 days
Granted (in shares)	55,500	58,500
Stock options \| 2019 Incentive Award Plan
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)	2,109,692
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	4 years
Aggregate intrinsic value, vested	$ 0.5	$ 0.4
Awards granted (in dollars per share)	$ 1.89	$ 2.42
Stock options, unrecognized compensation cost	$ 3.8
Stock options, cost not yet recognized, remaining weighted average vesting period	3 years
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)	565,187
Maximum employee payroll deduction percentage	20.00%

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

No definition available.

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- Definition

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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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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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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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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