STOCK BASED AND DEFERRED COMPENSATION - Narrative (Details)	6 Months Ended
Jun. 30, 2018 shares
Employees [Member] \| Non-vested stock awards [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for non-vested stock awards and stock options	5 years
Senior executive officers and non-employee directors [Member] \| Non-vested stock awards and performance-based awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for non-vested stock awards and stock options	3 years
2018 stock incentive plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized under stock compensation plan (up to) (in shares)	1,250,000
Remaining shares available for grant (in shares)	1,250,000
2006 stock incentive plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized under stock compensation plan (up to) (in shares)	5,350,000
Remaining shares available for grant (in shares)	643,793

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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.

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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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