Issuance of option grants to purchase common stock shares.

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- Definition

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

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

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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- Definition

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

+ References

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- Definition

The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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- Definition

Disclosure of information about share-based payment arrangement.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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- Definition

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

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- Definition

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.

+ References

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

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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- Definition

The increase or decrease in number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding, including vested options.

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- Definition

Number of shares issued under share-based payment arrangement.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

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Stock Based Compensation - Additional Information (Detail) - USD ($)			12 Months Ended
	Jun. 09, 2021	Jun. 13, 2018	Dec. 31, 2021	Dec. 31, 2020	Feb. 28, 2021
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Weighted average grant date fair value of stock options			$ 4.00	$ 5.20
Aggregate intrinsic value of options exercised			$ 3,000	$ 100,000
Fair value of options vested			$ 2,600,000	3,000,000.0
Number of common stock available for future grant			3,333,791
Total stock-based compensation			$ 3,405,000	3,627,000
Employee Stock Option
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Unrecognized employee stock based compensation expense			$ 3,900,000
Unrecognized employee stock based compensation expense, period for recognition			2 years 5 months 26 days
2018 Omnibus Incentive Plan
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Increase in number of shares of common stock reserved for issuance	2,500,000
Common Stock, Capital Shares Reserved for Future Issuance	5,300,000
2018 Omnibus Incentive Plan \| Performance Based Stock Option Grants
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Issuance of option grants to purchase common stock shares					647,000
2018 Employee Stock Purchase Plan
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Maximum employee subscription rate		15.00%
Number of common stock available for future grant			235,469
Number of common stock authorized for issuance			359,545
Number of common stock stock issued			64,975
Proceeds from Issuance			$ 300,000
Total stock-based compensation			$ 100,000	$ 100,000
2018 Employee Stock Purchase Plan \| Maximum
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Percentage of fair market value of common stock		85.00%