STOCK OPTIONS - Summary of Stock Options (Details) - $ / shares		12 Months Ended
Jan. 29, 2020	Dec. 31, 2020	Dec. 31, 2019
Number of options
Outstanding, beginning of period (in shares)		3,966,858	3,254,779
Granted (in shares)	700,000	1,376,900	1,379,500
Exercised (in shares)		(112,965)	(410,635)
Cancelled and forfeited (in shares)		(291,850)	(256,785)
Outstanding, end of period (in shares)		4,938,943	3,966,858
Weighted average exercise price
Outstanding, beginning of period (in dollars per share)		$ 4.67	$ 3.18
Granted (in dollars per share)		7.94	7.70
Exercised (in dollars per share)		3.37	2.99
Cancelled and forfeited (in dollars per share)		7.19	4.76
Outstanding, end of period (in dollars per share)		$ 5.46	$ 4.67

For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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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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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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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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