GOODWILL (GOODWILL ROLLFORWARD) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Goodwill [Line Items]
Beginning balance, goodwill	$ 301,694
Acquisitions / Adjustments Increase (Decrease)	8,408
Effect of Foreign Currency	(4,571)
Ending balance, goodwill	305,531
TTEC Digital
Goodwill [Line Items]
Beginning balance, goodwill	66,275
Acquisitions / Adjustments Increase (Decrease)	8,662
Effect of Foreign Currency	(1,068)
Ending balance, goodwill	73,869
TTEC Engage
Goodwill [Line Items]
Beginning balance, goodwill	235,419
Acquisitions / Adjustments Increase (Decrease)	(254)
Effect of Foreign Currency	(3,503)
Ending balance, goodwill	$ 231,662

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
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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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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Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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