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

No definition available.

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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 option under share-based payment arrangement.

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Amount of tax benefit from exercise of option under share-based payment arrangement.

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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 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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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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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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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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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		12 Months Ended
	Jun. 14, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Oct. 31, 2020
Stock-based compensation
Common stock, shares issued		9,422,089	9,993,135
Options granted (in shares)		522,337	552,153
Warrant & stock option exercises (in shares)		0	6,600
Remaining unrecognized compensation cost of non-vested stock options		$ 2,000
Weighted-average remaining requisite service period of recognition of unrecognized compensation cost		1 year 4 months 24 days
Excess income tax benefits		$ 0	$ 0
Minimum
Stock-based compensation
Options granted, grant date fair value		$ 1.76
Stock awards vesting period		3 years
Maximum
Stock-based compensation
Options granted, grant date fair value			$ 3.36
Stock awards vesting period		4 years
Board Director [Member]
Stock-based compensation
Stock awards vesting period		1 year
Stock options
Stock-based compensation
Options granted (in shares)		522,337	552,153
Warrant & stock option exercises (in shares)			6,600
Restricted Stock Units (RSUs)
Stock-based compensation
Restricted Stock Units outstanding/unvested		137,657	18,992	16,524
Restricted stock units, grant date fair value		$ 1.88	$ 6.69	$ 11.30
Restricted Stock Units, Granted		118,665	18,992
Vested stock units		17,409
Restricted Stock Units (RSUs) \| Employees
Stock-based compensation
Stock awards vesting period		3 years	3 years
Restricted Stock Units (RSUs) \| Board Director [Member]
Stock-based compensation
Stock awards vesting period		1 year	1 year
2018 Equity Incentive Plan (the "2018 Plan") [Member]
Stock-based compensation
Number of additional shares authorized	500,000
Number of shares reserved for issuance		392,396
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 authorized shares					200,000
Number of shares reserved for issuance		80,000
Common stock, shares issued		120,000