STOCK BASED AND DEFERRED COMPENSATION - Summary of Compensation Expense and Stock Award Activity (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Summary of compensation expense and stock award activity | |||
| Stock-based compensation expense | $ 12,056 | $ 13,741 | $ 15,781 |
| Cash received by Company from exercises | $ 0 | $ 232 | $ 2,886 |
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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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