STOCK-BASED COMPENSATION - Stock option and restricted stock option activity (Details) - Options [Member] - shares shares in Thousands	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Option Shares
Outstanding at the beginning of the period (in shares)	757	759
Granted (in shares)	7	160
Exercised (in shares)	(8)	(114)
Forfeited (in shares)	(13)	(18)
Expired (in shares)		(1)
Outstanding at the end of the period (in shares)	743	786

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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- Definition

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.

+ References

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

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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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.

+ References

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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