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BASIS OF PRESENTATION AND ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands | Jun. 30, 2018 | Dec. 31, 2017
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Recently Adopted Accounting Standards [Abstract] |  |
Retained earnings | $ 154,985 | $ 147,807
ASU 2014-09 [Member] |  |
Recently Adopted Accounting Standards [Abstract] |  |
Retained earnings |  | 151,256
Adjustments Due to ASC 606 [Member] | ASU 2014-09 [Member] |  |
Recently Adopted Accounting Standards [Abstract] |  |
Retained earnings | $ 4,096 | $ 3,449

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