RESTRUCTURING AND INTEGRATION CHARGES AND IMPAIRMENT LOSSES (LIABILITY CLASSIFICATION TABLE) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Restructuring Cost and Reserve [Line Items]
Reduction in force	$ 800	$ 117	$ 800	$ 560
Facility exit charges	925	676	1,327	771
Restructuring charges, net	1,725	793	2,126	1,331
TTEC Digital
Restructuring Cost and Reserve [Line Items]
Reduction in force	858	114	858	321
Facility exit charges			8
TTEC Engage
Restructuring Cost and Reserve [Line Items]
Reduction in force	(58)	3	(58)	239
Facility exit charges	$ 925	$ 676	$ 1,319	$ 771

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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