RESTRUCTURING AND INTEGRATION CHARGES AND IMPAIRMENT LOSSES (LIABILITY CLASSIFICATION TABLE) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Restructuring Cost and Reserve [Line Items]
Reduction in force	$ 187	$ 1,811	$ 391	$ 1,854
Facility exit charges	847		1,492	126
Restructuring charges, net	1,034	3,593	1,883	3,762
Customer Management Services [Member]
Restructuring Cost and Reserve [Line Items]
Reduction in force	187	1,797	340	1,761
Facility exit charges	851		851	42
Customer Growth Services [Member]
Restructuring Cost and Reserve [Line Items]
Facility exit charges	$ (4)		641
Customer Technology Services [Member]
Restructuring Cost and Reserve [Line Items]
Reduction in force		$ 14		93
Facility exit charges				$ 84
Customer Strategy Services [Member]
Restructuring Cost and Reserve [Line Items]
Reduction in force			$ 51