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Share-Based Compensation Arrangement By Share-Based Payment Award, Non-Option Equity Instruments, Exercised, Aggregate Intrinsic Value

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Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Issued

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable Period

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Share-based Compensation Arrangement by Share-based Payment Award, Period Of Exercise Price

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Unrecognized Compensation Costs Related to RSU Awards

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Unrecognized Compensation Costs Related to Unvested Stock Options

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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 cash inflow from exercise of 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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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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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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Number of non-option equity instruments exercised by participants.

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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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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 grant-date intrinsic value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

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

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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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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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

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SHARE-BASED PAYMENTS - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable options, weighted average remaining contractual term	2 years 2 months 19 days
Number of options (in shares)	942,882	1,609,087	1,487,433	1,732,754
Number of exercisable options (in shares)	729,565
Outstanding options, weighted average exercise price (in dollars per share)	$ 2.79	$ 2.91	$ 3.43	$ 3.84
Number of exercises in period (in shares)	775,814	302,707	54,805
Stock exercised, intrinsic value	$ 2,880	$ 420	$ 50
Grants in period, weighted average exercise price (in dollars per share)	$ 3.99	$ 1.77	$ 2.92
Exercise price (in USD per share)	$ 2.95	$ 1.97	$ 2.27
Cash received from exercise of stock options	$ 2,375	$ 491	$ 146
Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized (in shares)	15,626,220
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	2 years
Award exercise period	5 years
Unrecognized compensation costs related to unvested stock options	$ 60
Recognition period for unrecognized compensation costs	1 year 1 month 17 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Number of RSUs granted in period (in shares)	440,000	740,000	730,000
Grants in period, grant date intrinsic value (in dollars per share)	$ 2,670,000	$ 1,210,000	$ 2,510,000
Unrecognized compensation costs related to RSU awards	$ 680
Recognition period for unrecognized compensation costs	1 year 8 months 1 day
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			5 years
Stock options granted in period (in shares)	0	0	2,200,000
Grants in period, weighted average exercise price (in dollars per share)			$ 1.25
Unrecognized compensation costs related to RSU awards	$ 0
Recognition period for unrecognized compensation costs	0 days
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Issued	5,643
Exercised (in shares)	(48,201)	0	0
Share-Based Compensation Arrangement By Share-Based Payment Award, Non-Option Equity Instruments, Exercised, Aggregate Intrinsic Value	$ 310
Payments For Exercise of Stock Appreciation Rights	$ 260
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options, weighted average exercise price (in dollars per share)	$ 1.70	$ 1.70	$ 1.70	1.70
Grants in period, weighted average exercise price (in dollars per share)	3.89	1.76
Exercise price (in USD per share)	1.70	1.70	1.70
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options, weighted average exercise price (in dollars per share)	8.41	15.61	15.61	$ 15.61
Grants in period, weighted average exercise price (in dollars per share)	8.41	3.06
Exercise price (in USD per share)	$ 7.42	$ 2.92	2.92
Maximum \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable options, weighted average remaining contractual term	10 years
Common Stock \| Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period, weighted average exercise price (in dollars per share)			2.92
Share-based Compensation Award, Tranche One \| Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period, weighted average exercise price (in dollars per share)			5.00
Share-based Compensation Award, Tranche Two \| Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period, weighted average exercise price (in dollars per share)			$ 7.00
Exercised in period (in shares)	90 days		90 days
Share-based Compensation Award, Tranche Three \| Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period, weighted average exercise price (in dollars per share)			$ 10.00
Exercised in period (in shares)			90 days