Common stock capital shares reserved for future issuance new shares.

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Increase decrease in stock based compensation expense.

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Share based compensation arrangement by share based payment award award vesting date.

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Share based compensation arrangement by share based payment award award vesting period installments.

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

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Aggregate number of common shares reserved for future issuance.

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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 nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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The number of grants made 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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Number of shares authorized for issuance under share-based payment arrangement.

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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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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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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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Stock-Based Payments - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended			9 Months Ended
	Apr. 01, 2021	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jul. 02, 2021	May 25, 2021	May 15, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of stock option issued					554,615
Share-based compensation expense		$ 740		$ 450	$ 3,896	$ 2,021
Chief Executive Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Reduction in stock-based compensation expense		100			100
Chief Operating Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense		500			$ 500
Employee and Director Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of stock option issued					554,615
Stock option forfeited					13,200
Unrecognized compensation cost related to non-vested stock options outstanding		3,000			$ 3,000
Weighted-average remaining vesting period					3 years 4 months 24 days
Unrecognized compensation cost related to Performance-based stock options		1,200			$ 1,200
Weighted average grant date fair value					$ 10.67
Consultants Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of stock option issued					0
Unrecognized compensation cost related to non-vested stock options outstanding		$ 3			$ 3
Weighted-average remaining vesting period					1 month 6 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares granted					9,871
Restricted Stock Units \| Board of Directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares granted					6,343
Vesting period in installments					12 months
2018 Omnibus Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares authorized and approved to issue under plan								565,000	153,031
Common stock shares available for issuance									85,714
Common stock remaining available for grant		139,139			139,139
2018 Omnibus Incentive Plan \| Restricted Stock Units \| Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares granted			2,668
Scheduled to vest date			Oct. 02, 2021
2018 Omnibus Incentive Plan \| Unrestricted Stock \| Officer \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares granted	5,337
2016 Omnibus Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares available for issuance									67,317
2021 Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock remaining available for grant		80,000			80,000
2021 Inducement Plan \| Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares available for issuance							100,000