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 cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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

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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 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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Number of grantees affected by modification of award under share-based payment arrangement.

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Number of shares for which recognition of cost was accelerated for award under share-based payment arrangement.

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Amount of cost expensed and capitalized for award under share-based payment arrangement.

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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 shares related to Restricted Stock Award forfeited during the period.

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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)	1 Months Ended	3 Months Ended	12 Months Ended
Stock-Based Compensation (Narrative) (Details)	Sep. 30, 2020 director shares	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Oct. 31, 2020 shares
Minimum [Member]
Stock-based compensation
Stock awards vesting period			3 years
Maximum [Member]
Stock-based compensation
Stock awards vesting period			4 years
Board Director [Member]
Stock-based compensation
Stock awards vesting period			1 year
Stock Options [Member]
Stock-based compensation
Options granted, grant date fair value \| $ / shares			$ 3.47	$ 11.51
Options granted (in shares)			511,800	77,514
Stock option exercised (in shares)			0	0
Number of former directors \| director	2
Number of accelerated stock options	10,400
Excess income tax benefits \| $			$ 0	$ 0
Modification charges recognized \| $		$ 20,000
Remaining unrecognized compensation cost of non-vested stock options \| $			$ 1,900,000
Weighted-average remaining requisite service period of recognition of unrecognized compensation cost			2 years 7 months 28 days
Stock Options [Member] \| Minimum [Member]
Stock-based compensation
Stock awards vesting period	1 year
Stock Options [Member] \| Maximum [Member]
Stock-based compensation
Stock awards vesting period	3 years
Restricted Stock Units (RSUs) [Member]
Stock-based compensation
Restricted Stock Units outstanding			16,524	14,000
Stock units forfeited			1,414
Vested stock units
Compensation cost recognized \| $			$ 0
2018 Equity Incentive Plan (the "2018 Plan") [Member]
Stock-based compensation
Number of authorized shares			775,000
Number of additional shares authorized			35,494
Number of shares reserved for issuance			328,035
2018 Equity Incentive Plan (the "2018 Plan") [Member] \| Minimum [Member]
Stock-based compensation
Stock awards vesting period			1 year
2018 Equity Incentive Plan (the "2018 Plan") [Member] \| Maximum [Member]
Stock-based compensation
Stock awards vesting period			4 years
2018 Equity Incentive Plan (the "2018 Plan") [Member] \| Stock Options [Member]
Stock-based compensation
Life of stock option awards granted			10 years
Options granted (in shares)			391,800	77,514
Inducement Equity Incentive Plan 2020 [Member]
Stock-based compensation
Number of shares reserved for issuance			80,000		200,000
Options granted (in shares)			120,000
Inducement Equity Incentive Plan 2020 [Member] \| Stock Options [Member]
Stock-based compensation
Options granted (in shares)			120,000