STOCK-BASED COMPENSATION (Details 4)	Dec. 31, 2020 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sub-limit for all types of stock awards included in available to be issued stock options (in shares)	472,630
2000 long term incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for Issuance (in shares)	18,666
Number of shares available for grant or purchase (in shares)	0
2003 long term incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for Issuance (in shares)	178,284
Number of shares available for grant or purchase (in shares)	0
2006 long term incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for Issuance (in shares)	93,190
Number of shares available for grant or purchase (in shares)	0
2009 long term incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for Issuance (in shares)	1,510,954
Number of shares available for grant or purchase (in shares)	0
2014 long term incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for Issuance (in shares)	1,784,213
Number of shares available for grant or purchase (in shares)	0
2016 long term incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for Issuance (in shares)	1,967,666
Number of shares available for grant or purchase (in shares)	0
2018 long term incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for Issuance (in shares)	9,933,512
Number of shares available for grant or purchase (in shares)	4,834,380
Long Term Incentive Stock Option Plan Reserved for Issuance
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for Issuance (in shares)	15,486,485
Long Term Incentive Stock Option Plan Available for Grant or Purchase
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant or purchase (in shares)	4,834,380
1997 stock plan for non-employee directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for Issuance (in shares)	453,323
Number of shares available for grant or purchase (in shares)	176,088

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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Number of shares authorized for issuance under share-based payment arrangement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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