Weighted average remaining life of warrants or rights outstanding.

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- Definition

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

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of warrants or rights outstanding.

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No definition available.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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

Amount of cash inflow from exercise of option under share-based payment arrangement.

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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

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.

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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

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

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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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Share-Based Compensation - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Aug. 03, 2018	Dec. 03, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding to purchase shares of common stock (in shares)	21,580,997		21,843,781
Warrants outstanding (in shares)	950,000		1,100,000
Share-based payments expense	$ 2,400,000	$ 2,000,000
Unrecognized compensation expense related to non-vested share options	$ 10,700,000
Weighted average period for recognition related to non-vested stock options (in years)	1 year 5 months 1 day
Total intrinsic value of shares exercised	$ 0	500,000
Total fair value of vested shares	$ 2,200,000	1,900,000
Weighted average exercise price of warrants (in dollars per share)	$ 4.24
Weighted average remaining life of warrants (in years)	4 months 24 days
2010 Stock Incentive Plan ("the Plan")
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance (in shares)				56,800,000	31,500,000
Number of options available for issuance (in shares)	17,600,000
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding to purchase shares of common stock (in shares)	21,600,000
Cash received from options exercised	$ 0	$ 300,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to unvested restricted shares	$ 0