STOCK-BASED COMPENSATION (Details 4)	Dec. 31, 2018 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)	1,989,000
2000 long term incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for Issuance (in shares)	44,130
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)	215,584
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)	278,270
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)	1,873,421
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)	2,098,802
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)	2,326,334
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)	9,263,665
Number of shares available for grant or purchase (in shares)	9,252,665
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)	16,100,206
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)	9,252,665
1997 stock plan for non-employee directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved for Issuance (in shares)	536,295
Number of shares available for grant or purchase (in shares)	375,245

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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

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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