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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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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GOODWILL (NARRATIVE) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
GOODWILL (NARRATIVE) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
ValuationAllowanceForImpairmentOfRecognizedServicingAssetsLineItems
Goodwill		$ 203,823		$ 204,633
Impairment losses		3,569	$ 1,120
Other Intangible Assets [Member]
ValuationAllowanceForImpairmentOfRecognizedServicingAssetsLineItems
Impairment losses	$ 2,000
TTEC Digital
ValuationAllowanceForImpairmentOfRecognizedServicingAssetsLineItems
Goodwill		$ 65,544		$ 66,158
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