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Share-based Compensation Arrangement by Share-based Payment Award, Percent Of Base Salary

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Share-based Compensation Arrangement by Share-based Payment Award, Shares Received Per Award

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Share-based Payment Arrangement, Expense, On Cash Bonus

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

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Aggregate number of common shares reserved for future issuance.

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

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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 nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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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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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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

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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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Number of options vested.

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SHARE-BASED COMPENSATION - Narrative (Details) - USD ($)	1 Months Ended		12 Months Ended
	May 31, 2021	Jun. 30, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)			15,703,000	10,147,000	6,236,000	3,942,000
Share-based compensation expense			$ 5,143,000	$ 1,757,000	$ 1,237,000
Unrecognized compensation cost, non-vested stock options			$ 10,400,000
Weighted average period unvested stock to be recognized			2 years 8 months 12 days
Weighted-average grant-date fair value of stock options granted (in dollars per share)			$ 2.16	$ 0.56	$ 1.02
Share-based Payment Arrangement, Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)			2,800,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance (in shares)			15,703,000
Share-based compensation expense			$ 4,600,000	$ 1,800,000	$ 1,200,000
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance (in shares)			3,041,000	0
Unvested weighted average remaining contractual life			9 years 9 months
Unvested grant restricted stock units (in shares)			2,482,000	0	0
Performance-Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			4 years
Unrecognized compensation expense			$ 400,000
Unvested weighted average remaining contractual life			9 years 9 months
Unvested grant restricted stock units (in shares)			559,000
2014 Stock Incentive Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance (in shares)	12,000,000	7,900,000
Shares reserved for future issuance (in shares)			8,900,000
Award vesting period			4 years
Expected term			10 years
Options outstanding (in shares)			12,800,000
Retention Program \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares received per award (in shares)			1
Share-based compensation expense			$ 500,000	$ 0	$ 0
Expense related to cash bonus			$ 600,000
Retention Program \| Performance-Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares received per award (in shares)			1
Percent of base salary			50.00%
Stock Incentive Plan 2009 \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term			10 years
Vested stock options outstanding (in shares)			100,000
Vesting on the First Anniversary of Date of Grant \| 2014 Stock Incentive Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of original number of shares subject to the option vesting			25.00%
Vesting at End of Each Successive Three-Month Period Thereafter \| 2014 Stock Incentive Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of original number of shares subject to the option vesting			6.25%