NET INCOME (LOSS) PER COMMON SHARE - Disclosure of Anti-Dilutive Shares (Details) - $ / shares shares in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excluded shares as anti-dilutive when reporting a net loss	0	0	73	0
Price range of options: from (in dollars per share)			$ 3.54
Price range of options: to (in dollars per share)			$ 13.98
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excluded shares as anti-dilutive when reporting a net loss	609	545	609	549
Price range of options: from (in dollars per share)	$ 3.54	$ 6.43	$ 3.54	$ 6.43
Price range of options: to (in dollars per share)	$ 13.98	$ 13.98	$ 13.98	$ 13.98
RSUs \| Restricted Stock Units Service Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excluded shares as anti-dilutive when reporting a net loss	2,464	3,555	2,626	1,939
RSUs \| Restricted Stock Units Service And Market Conditions But Market Not Met
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excluded shares as anti-dilutive when reporting a net loss	199	70	199	70

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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