IMPAIRMENT OF ASSETS (NARRATIVE) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Impaired Long-Lived Assets Held and Used [Line Items]
Impaired Long-Lived Assets Held and Used, Asset Description			Assumptions included the amount and timing of estimated future cash flows and assumed discount rates.
Impaired Long-Lived Assets Held and Used, Method for Determining Fair Value			The amount of impairment recognized is the difference between the carrying value of the asset group and its fair value. To determine fair value, the Company used Level 3 inputs in its discounted cash flows analysis.
Asset Impairment Charges	$ 441	$ 4,688	$ 1,966	$ 241,544
TTEC Digital \| Leasehold Improvements Right of Use Lease Assets Capitalized Software Certain Computer Equipment [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairment Charges	0	400	200	2,900
TTEC Engage \| Leasehold Improvements Right of Use Lease Assets Capitalized Software Certain Computer Equipment [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairment Charges	$ 400	$ 4,300	$ 1,700	$ 5,100

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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