GOODWILL (GOODWILL ROLLFORWARD) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Beginning balance, goodwill	$ 209,727	$ 132,681
Acquisitions / Adjustments	1,107	(73,273)
Effect of Foreign Currency	(6,201)	3,773
Ending balance, goodwill	204,633	209,727
Customer Management Services [Member]
Goodwill [Line Items]
Beginning balance, goodwill	119,497	42,589
Acquisitions / Adjustments	(125)	(73,934)
Effect of Foreign Currency	(5,336)	2,974
Ending balance, goodwill	114,036	119,497
Customer Growth Services [Member]
Goodwill [Line Items]
Beginning balance, goodwill	24,439	24,439
Acquisitions / Adjustments	0	0
Ending balance, goodwill	24,439	24,439
Customer Technology Services [Member]
Goodwill [Line Items]
Beginning balance, goodwill	40,839	41,500
Acquisitions / Adjustments	1,232	661
Effect of Foreign Currency	(92)
Ending balance, goodwill	41,979	40,839
Customer Strategy Services [Member]
Goodwill [Line Items]
Beginning balance, goodwill	24,952	24,153
Acquisitions / Adjustments	0	0
Effect of Foreign Currency	(773)	799
Ending balance, goodwill	$ 24,179	$ 24,952

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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