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

No definition available.

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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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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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No definition available.

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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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No definition available.

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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) - USD ($)	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Oct. 31, 2020	Dec. 31, 2019
Minimum [Member]
Stock-based compensation
Stock awards vesting period		1 year
Maximum [Member]
Stock-based compensation
Stock awards vesting period		4 years
Stock Options [Member]
Stock-based compensation
Options granted (in shares)		154,653	56,400
Stock option exercised (in shares)		0	0
Stock Options [Member] \| Minimum [Member]
Stock-based compensation
Options granted, grant date fair value		$ 3.44	$ 2.48
Stock Options [Member] \| Maximum [Member]
Stock-based compensation
Options granted, grant date fair value		$ 6.14	$ 3.95
Restricted Stock Units (RSUs) [Member]
Stock-based compensation
Restricted Stock Units outstanding	35,439	35,439		3,938		14,000
Restricted stock units, grant date fair value	$ 8.82	$ 8.82
Stock units forfeited				1,491
Compensation cost recognized	$ 0
Restricted Stock Units (RSUs) [Member] \| Fulfillment of Certain Clinical Conditions [Member]
Stock-based compensation
Restricted Stock Units outstanding	16,447	16,447
Restricted Stock Units (RSUs) [Member] \| Board Director [Member]
Stock-based compensation
Restricted Stock Units outstanding	18,992	18,992
Restricted stock units, grant date fair value	$ 6.69	$ 6.69
Restricted Stock Units (RSUs) [Member] \| Board Director [Member] \| Minimum [Member]
Stock-based compensation
Stock awards vesting period	1 year
Restricted Stock Units (RSUs) [Member] \| Board Director [Member] \| Maximum [Member]
Stock-based compensation
Stock awards vesting period	3 years
2018 Equity Incentive Plan (the "2018 Plan") [Member]
Stock-based compensation
Number of shares reserved for issuance	891,015	891,015
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
Inducement Equity Incentive Plan 2020 [Member]
Stock-based compensation
Number of shares reserved for issuance	80,000	80,000			200,000
Options granted (in shares)		120,000