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ACQUISITIONS AND DIVESTITURES 4 (NARRATIVE) (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
	Jun. 30, 2017	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Gain on sale of business						$ 600				$ 0	$ 908	$ 0
Impairment losses		$ 332	$ 0	$ 0	$ 1,120	$ 5,322	$ 0	$ 0	$ 0	1,452	5,322	32,050
Proceeds from sale of business										0	636	0
Other nonoperating income expense										$ (11,618)	$ 1,869	$ 6,855
Technology Solutions Group [Member]
Business Acquisition [Line Items]
Gain on sale of business		$ 300						30
Impairment losses								$ 700
Proceeds from sale of business	$ 250						141
Customer Technology Services [Member] \| TeleTech Spain Holdings SL [Member]
Business Acquisition [Line Items]
Other nonoperating income expense							$ 3,200