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FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (FV - Level 3) (Details) - Contingent Consideration - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Fair Value of liabilities level 3 hierarchy |  |
Balance beginning of period | $ 6,970 | $ 6,775
Payments | (3,528) |
Change in fair value included in operating expenses | 1,030 | 195
Balance at end of period | $ 4,472 | $ 6,970

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