Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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GOODWILL (NARRATIVE) (Details) - USD ($) $ in Thousands	3 Months Ended
GOODWILL (NARRATIVE) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2019
ValuationAllowanceForImpairmentOfRecognizedServicingAssetsLineItems
Goodwill	$ 305,531			$ 301,694
Impairment losses	696		$ 1,506
Other Intangible Assets [Member]
ValuationAllowanceForImpairmentOfRecognizedServicingAssetsLineItems
Impairment losses		$ 2,000
TTEC Digital
ValuationAllowanceForImpairmentOfRecognizedServicingAssetsLineItems
Goodwill	$ 73,869			$ 66,275
Goodwill, Impaired, Method for Fair Value Determination	During the Company's annual impairment testing as of December 1, 2019, the Company identified triggering events that could lead to impairment of goodwill for the Digital Consulting reporting unit, including lower revenues and profits than had been anticipated over the past two years. The carrying value of Digital Consulting was $39.7 million at December 1, 2019, including approximately $24.3 million of goodwill. Based on the Company's assessment, the estimated fair value of the Digital Consulting reporting unit exceeded its carrying value by approximately 26%, but based on additional sensitivity analysis, the amount of cushion could fall to 0% or below if the performance of the business does not improve as expected. The estimate of fair value was based on generally accepted valuation techniques and information available at the date of the assessment, which incorporated management's assumptions about expected revenues and future cash flows and available market information for comparable companies.
TTEC Digital \| Other Intangible Assets [Member] \| Customer Relationships [Member]
ValuationAllowanceForImpairmentOfRecognizedServicingAssetsLineItems
Impairment losses		400
TTEC Digital \| Other Intangible Assets [Member] \| Intellectual Property [Member]
ValuationAllowanceForImpairmentOfRecognizedServicingAssetsLineItems
Impairment losses		$ 200