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STOCK-BASED COMPENSATION PLANS - Summary of our unvested stock options (Details) - Non vested Share Awards [Member] - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Non-vested Shares Under Option, Beginning Balance	890	569
Non-vested Shares Under Option, Granted	14	653
Non-vested Shares Under Option, Vested	(251)	(169)
Non-vested Shares Under Option, Forfeited	(222)	(163)
Non-vested Shares Under Option, Ending Balance	431	890
Weighted Average Grant Date Fair Value, Beginning Balance	$ 4.03	$ 1.44
Weighted Average Grant Date Fair Value, Granted	8.88	5.12
Weighted Average Grant Date Fair Value, Vested	3.34	1.24
Weighted Average Grant Date Fair Value, Forfeited	4.36	2.44
Weighted Average Grant Date Fair Value, Ending Balance	$ 4.35	$ 4.03

X

- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ 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 (d)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Number of non-vested options outstanding.

+ References

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- Definition

Number of non-vested options forfeited.

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- Definition

Weighted average grant-date fair value of non-vested options forfeited.

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- Definition

Weighted average grant-date fair value of non-vested options outstanding.

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- Definition

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Weighted average grant-date fair value of options vested.

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