Common stock issuance description.

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- Definition

Number of equity incentive plans.

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- Definition

Share-based compensation arrangement by share based payment award, stock offering period.

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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.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

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No definition available.

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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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-Topic 718
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-Section 50
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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

Gross number of share options (or share units) granted during the period.

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No definition available.

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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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.

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- Definition

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

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No definition available.

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- Definition

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

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- Definition

Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

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Stock-Based Compensation - Additional Information (Details) $ in Millions	1 Months Ended	12 Months Ended
	Feb. 28, 2019 IncentivePlan shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($) shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of equity incentive plans \| IncentivePlan	2
Number of common shares, granted		1,499,000
Number of shares available for future grant		1,400,000	900,000
Common Stock options exercised		525,000
Intrinsic value of options exercised \| $		$ 5.4	$ 0.8
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock options exercised			100,000
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total fair value of restricted stock units vested during the period \| $		$ 1.9	$ 0.1
2015 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Reverse stock split	one-for-five
Common stock issuance, description		On January 1 of each year through 2025, the number of shares authorized for issuance under the 2015 Plan automatically increases by an amount equal to the lower of (i) 4 percent of the total number of shares of common stock outstanding on December 31 of the preceding calendar year, or (ii) a lower number determined by the Board of Directors.
Percentage of shares issued on common stock outstanding		4.00%
2009 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares, granted	0
2019 Plan, 2015 Equity Incentive Plan and Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option expiration period		10 years
Vesting percentage		25.00%
Vesting period		3 years
2019 Plan, 2015 Equity Incentive Plan and Stock Incentive Plan \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of exercise price to fair market value common stock on grant date		100.00%
2019 Plan, 2015 Equity Incentive Plan and Stock Incentive Plan \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		33.33%
Vesting period		2 years
2015 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant		700,000
Common stock issuance, description		On January 1 of each year through 2025, the number of shares authorized for issuance under the ESPP, automatically increases by an amount equal to the lower of (i) 1 percent of the total number of shares of common stock outstanding on December 31 of the preceding calendar year, or (ii) a lower number determined by the Board of Directors.
Percentage of shares issued on common stock outstanding		1.00%
Percentage of exercise price to fair market value common stock on grant date		85.00%
Offering period		6 months