GOODWILL (GOODWILL ROLLFORWARD) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($)
Goodwill [Line Items]
Beginning balance, goodwill	$ 206,694
Acquisitions / Adjustments	1,337
Effect of Foreign Currency	(6,205)
Ending balance, goodwill	201,826
Customer Management Services [Member]
Goodwill [Line Items]
Beginning balance, goodwill	119,497
Acquisitions / Adjustments	(125)
Effect of Foreign Currency	(5,586)
Ending balance, goodwill	113,786
Customer Growth Services [Member]
Goodwill [Line Items]
Beginning balance, goodwill	24,439
Ending balance, goodwill	24,439
Customer Technology Services [Member]
Goodwill [Line Items]
Beginning balance, goodwill	40,839
Acquisitions / Adjustments	1,462
Effect of Foreign Currency	(78)
Ending balance, goodwill	42,223
Customer Strategy Services [Member]
Goodwill [Line Items]
Beginning balance, goodwill	21,919
Effect of Foreign Currency	(541)
Ending balance, goodwill	$ 21,378

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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