Share based compensation arrangement by share based payment award award granted period.

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Share based compensation arrangement by share based payment award award vesting rights percentage upon achievement of milestones.

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Share based compensation arrangement by share based payment award options fair value exercise price percentage minimum under condition two.

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Share based compensation arrangement by share based payment award options minimum holding percentage under condition.

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

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Number of common shares reserved for future issuance related to deferred compensation arrangements with individuals.

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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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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

Discount rate from fair value on purchase date that participants pay for shares.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

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

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

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- Definition

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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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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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

Number of options outstanding, including both vested and non-vested options.

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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.

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No definition available.

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Number of shares issued under share-based payment arrangement.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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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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Equity Incentive Plans - Additional Information (Details) - USD ($)			1 Months Ended	12 Months Ended
	Jan. 03, 2022	Jan. 20, 2021	Sep. 30, 2014	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2010
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock are subject to options outstanding				8,324,000	8,637,000
Common stock fair value				$ 0.67
Weighted-average grant date fair value of options				$ 2.07	$ 5.09	$ 3.46
Total fair value of options vested				$ 9,400,000	$ 6,900,000	$ 6,700,000
Aggregate intrinsic value of options exercised				$ 23,000	$ 200,000	$ 300,000
Weighted-average remaining contractual term, exercisable options				4 years 11 months 15 days
Weighted-average remaining contractual term, vested and expected to vest options				6 years 1 month 24 days
Unrecognized compensation expense related to unvested awards				$ 8,900,000
Weighted-average period to recognize compensation expense				2 years 4 months 13 days
Number of stock awards issued				2,190,000
Grant date fair value of stock awards				$ 2.94
Number of stock vested				1,069,000
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity compensation plan, common stock outstanding percentage			1.00%
Number of shares available for issuance				680,893
Equity compensation plan, outstanding shares			250,000
Percentage of discount through payroll deductions to eligible employees to purchase common stock				15.00%
Percentage of fair value of common stock				85.00%
Shares of common stock issued to employees				1,085,757
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option vesting, year				4 years
Number of stock awards issued				582,056	0
Annual stock awards vesting percentage				25.00%
Fair value of other than options vested				$ 3,200,000
Number of stock vested					0
PSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of stock awards issued		1,607,812
Grant date fair value of stock awards		$ 2.98
Expense related to PSUs				$ 3,900,000
PSUs \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual stock awards vesting percentage	20.00%
Stock awards vesting percentage upon achievement of two goals	80.00%
2010 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of voting rights							10.00%
Minimum exercise price of incentive stock options							110.00%
Option granted, year							10 years
Option vesting, year							4 years
Shares of common stock are subject to options outstanding				365,000
2014 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option granted, year				10 years
Option vesting, year				4 years
Equity compensation plan, common stock outstanding percentage			4.00%
Common stock reserved for issuance				11,600,000
Number of shares available for issuance				1,821,000
2018 Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option granted, year				10 years
Option vesting, year				4 years
Common stock reserved for issuance				1,000,000
Number of shares available for issuance				811,000