Component of common stock capital shares reserved for future issuance.

No definition available.

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- Definition

Maximum amount of annual employee common stock purchase

+ References

No definition available.

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- Definition

Percentage of common share outstanding, as it relates to the number of shares reserved for future issuance calculation under the 2014 Stock Incentive Plan.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award options grants in period gross value grant date fair value.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award other than options grants in period gross value grant date fair value.

+ References

No definition available.

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- Definition

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

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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.

+ References

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

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

+ References

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- Definition

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.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

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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.

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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.

+ References

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- Definition

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.

+ References

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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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- Definition

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

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Stock-Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Aug. 06, 2020	Mar. 31, 2018
Share-Based Compensation
Fair value of vested stock options	$ 600,000	$ 600,000
Stock-based compensation expense	$ 2,545,000	1,293,000
Employee Stock Purchase Plan [Member]
Share-Based Compensation
Shares available for grant	2,623,655
Shares available for authorization			4,523,944
Percentage of full share price paid in purchase of common stock	85.00%
Maximum amount of annual employee common stock purchases	$ 25,000
Stock-based compensation expense	$ 100,000	100,000
Restricted Stock Units [Member]
Share-Based Compensation
Weighted-average period	2 years 1 month 6 days
Unrecognized compensation cost related to unvested stock options	$ 11,500,000
2014 Stock Option Plan [Member] \| Stock Options [Member]
Share-Based Compensation
Shares available for future issuance under stock incentive plan	823,529
Percentage of common shares outstanding	4.00%
Shares available for grant	1,415,266
Inducement Award Plan [Member]
Share-Based Compensation
Shares available for grant	4,009,361
Shares available for authorization				9,625,000
2006 and 2014 Stock Option Plans [Member] \| Stock Options [Member]
Share-Based Compensation
Aggregate fair value of options granted	$ 200,000	$ 600,000
Unrecognized compensation cost related to non-vested stock options	$ 3,200,000
Weighted-average period	2 years 4 months 24 days
2006 and 2014 Stock Option Plans and Inducement Plan [Member] \| Stock Options [Member]
Share-Based Compensation
Issuance of common stock from exercise of stock options (in shares)	0	42,626
Weighted average fair value of options granted	$ 0.33	$ 1.33
2006 and 2014 Stock Option Plans and Inducement Plan [Member] \| Restricted Stock Units [Member]
Share-Based Compensation
Aggregate fair value of restricted stock units granted	$ 3,600,000
Maximum [Member] \| 2006 Stock Option Plan [Member] \| Stock Options [Member]
Share-Based Compensation
Expiration period	10 years
Vesting period	4 years
Maximum [Member] \| 2014 Stock Option Plan [Member] \| Stock Options [Member]
Share-Based Compensation
Expiration period	10 years
Vesting period	4 years
Issuance of common stock from exercise of stock options (in shares)	35,000,000