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STOCK-BASED COMPENSATION, Stock Option Activity (Details) - Stock Options [Member] - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Number of Option Share [Roll Forward]
Outstanding, beginning balance (in shares)	3,988,000
Granted (in shares)	1,258,000	0
Cancelled (in shares)	(67,000)
Outstanding, ending balance (in shares)	5,179,000	0	3,988,000
Weighted Average Exercise Price per Share [Abstract]
Outstanding, beginning balance (in dollars per share)	$ 8.40
Granted (in dollars per share)	2.10
Cancelled (in dollars per share)	5.94
Outstanding, ending balance (in dollars per share)	$ 6.90		$ 8.40
Weighted Average Remaining Contractual Life [Abstract]
Weighted-average remaining contractual life, outstanding	9 years 3 months 25 days		9 years 4 months 17 days
Aggregate Intrinsic Value [Abstract]
Outstanding, beginning balance	$ 0
Granted	0
Outstanding, ending balance	$ 134,000		$ 0
Options Vested and Exercisable [Abstract]
Options vested and exercisable, Outstanding (in shares)	10,000
Options vested and exercisable, Weighted average exercise price (in dollars per share)	$ 10.26
Options vested and exercisable, weighted average remaining contractual life	9 years 9 months
Options vested and exercisable, aggregate intrinsic value	$ 0

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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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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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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 exercisable options that may 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 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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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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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