GOODWILL AND LONG-LIVED ASSETS (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
GOODWILL AND LONG-LIVED ASSETS [Abstract]
Impairment of long-lived assets	$ 0	$ 0
Changes in carrying amount of goodwill [Abstract]
Gross Goodwill Balance	117,176	117,176	$ 117,176	$ 117,176
Accumulated Impairment Losses	(102,640)	(102,640)	(102,640)	(102,640)
Adjustments	0	0
Net Goodwill Balance	$ 14,536	$ 14,536	$ 14,536	$ 14,536

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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