GOODWILL (GOODWILL ROLLFORWARD) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Beginning balance, goodwill	$ 204,633	$ 209,727
Acquisitions / Adjustments Increase (Decrease)	96,993	1,107
Effect of Foreign Currency	68	(6,201)
Ending balance, goodwill	301,694	204,633
TTEC Digital
Goodwill [Line Items]
Beginning balance, goodwill	66,158	65,791
Acquisitions / Adjustments Increase (Decrease)	0	1,232
Effect of Foreign Currency	117	(865)
Ending balance, goodwill	66,275	66,158
TTEC Engage
Goodwill [Line Items]
Beginning balance, goodwill	138,475	143,936
Acquisitions / Adjustments Increase (Decrease)	96,993	(125)
Effect of Foreign Currency	(49)	(5,336)
Ending balance, goodwill	$ 235,419	$ 138,475

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
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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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