Represents the grant date fair value of options granted during the reporting period.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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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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Number of share options (or share units) exercised during the current period.

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Stock Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Stock-based compensation
Common stock, shares issued	12,539,189		12,539,189
Options granted (in shares)	11,000	265,000
Options exercised (in shares)	0	0
Stock-based compensation costs before income taxes	$ 401	$ 380
Minimum
Stock-based compensation
Stock awards vesting period	1 year
Options granted, grant date fair value	$ 0.50	$ 2.62
Maximum
Stock-based compensation
Stock awards vesting period	4 years
Options granted, grant date fair value	$ 0.73	$ 2.90
Stock options
Stock-based compensation
Options granted (in shares)	11,000
Restricted Stock Units (RSUs)
Stock-based compensation
Stock awards vesting period	3 years
Restricted Stock Units, Granted	257,000		118,665
Restricted Stock Units outstanding/unvested	394,657
Restricted stock units, grant date fair value	$ 0.90		$ 1.11
2018 Equity Incentive Plan (the "2018 Plan") [Member]
Stock-based compensation
Number of shares reserved for issuance	142,158
Life of stock option awards granted	10 years
2018 Equity Incentive Plan (the "2018 Plan") [Member] \| Minimum
Stock-based compensation
Stock awards vesting period	1 year
2018 Equity Incentive Plan (the "2018 Plan") [Member] \| Maximum
Stock-based compensation
Stock awards vesting period	4 years
Inducement Equity Incentive Plan 2020 [Member]
Stock-based compensation
Number of shares reserved for issuance	80,000
Number of authorized shares	200,000
Common stock, shares issued	120,000