GOODWILL (GOODWILL ROLLFORWARD) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Goodwill [Line Items]
Beginning balance, goodwill	$ 204,633
Effect of Foreign Currency	547
Ending balance, goodwill	205,180
Customer Strategy Services [Member]
Goodwill [Line Items]
Beginning balance, goodwill	24,179
Effect of Foreign Currency	149
Ending balance, goodwill	24,328
Customer Technology Services [Member]
Goodwill [Line Items]
Beginning balance, goodwill	41,979
Effect of Foreign Currency	27
Ending balance, goodwill	42,006
Customer Growth Services [Member]
Goodwill [Line Items]
Beginning balance, goodwill	24,439
Ending balance, goodwill	24,439
Customer Management Services [Member]
Goodwill [Line Items]
Beginning balance, goodwill	114,036
Effect of Foreign Currency	371
Ending balance, goodwill	$ 114,407

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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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