GOODWILL (GOODWILL ROLLFORWARD) (DETAILS) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Goodwill [Line Items]
Beginning balance, goodwill	$ 129,648	$ 114,183
Acquisitions / Adjustments	73,273	(17,997)
Impairments		(1,363)
Effect of Foreign Currency	3,773	(1,169)
Ending balance, goodwill	206,694	129,648
Customer Management Services
Goodwill [Line Items]
Beginning balance, goodwill	42,589	23,218
Acquisitions / Adjustments	73,934	(21,030)
Impairments		(1,363)
Effect of Foreign Currency	2,974	(296)
Ending balance, goodwill	119,497	42,589
Customer Growth Services
Goodwill [Line Items]
Beginning balance, goodwill	24,439	24,439
Acquisitions / Adjustments	0	0
Ending balance, goodwill	24,439	24,439
Customer Technology Services
Goodwill [Line Items]
Beginning balance, goodwill	41,500	41,500
Acquisitions / Adjustments	(661)	0
Ending balance, goodwill	40,839	41,500
Customer Strategy Services
Goodwill [Line Items]
Beginning balance, goodwill	21,120	25,026
Acquisitions / Adjustments	0	3,033
Effect of Foreign Currency	799	(873)
Ending balance, goodwill	$ 21,919	$ 21,120

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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-Name Accounting Standards Codification
-Topic 350
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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