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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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No definition available.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. 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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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. 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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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. 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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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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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 option awards outstanding, 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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Number of share options (or share units) exercised during the current period.

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Stockholders' Equity - Company's Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
OUTSTANDING OPTIONS
Options forfeited	(73,859)
WEIGHTED-AVERAGE EXERCISE PRICE
Options forfeited	$ 1.98
2003 Stock Incentive Plan
OUTSTANDING OPTIONS
Outstanding at beginning of period	93,465
Options exercised	0	(3,785)
Outstanding at end of period	19,606		93,465
WEIGHTED-AVERAGE EXERCISE PRICE
Outstanding at beginning of period	$ 2.00
Outstanding at end of period	$ 2.07		$ 2.00
VESTED AND EXPECTED TO VEST
Weighted-Average Remaining Contractual Term	3 months 18 days		3 months 18 days
2013 Equity Incentive Plan
OUTSTANDING OPTIONS
Outstanding at beginning of period	5,655,457
Options granted	1,825,100
Options exercised	0	0
Options forfeited	(125,980)
Outstanding at end of period	7,354,577		5,655,457
WEIGHTED-AVERAGE EXERCISE PRICE
Outstanding at beginning of period	$ 8.30
Options granted	1.11
Options forfeited	11.13
Outstanding at end of period	$ 6.46		$ 8.30
VESTED AND EXPECTED TO VEST
Outstanding options	7,140,377
Weighted-Average Exercise Price	$ 6.62
Weighted-Average Remaining Contractual Term	6 years 9 months 18 days
Aggregate Intrinsic Value (in thousands)	$ 48
ADDITIONAL DISCLOSURES
Outstanding options exercisable at end of period	4,367,434
Weighted-average exercise price exercisable at end of period	$ 9.11
Weighted-average contractual term outstanding	6 years 9 months 18 days		6 years
Weighted-average contractual term (years) exercisable	5 years 2 months 12 days
Aggregate intrinsic value (in thousands) outstanding at end of period	$ 55