ACQUISITIONS AND DIVESTITURES (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Assets and Liabilities Held for Sale [Line Items]
Total assets held for sale	$ 9,163	$ 7,835
Total liabilities held for sale	3,788	$ 1,322
Business Unit From Customer Growth Services And Customer Strategy Services Segments | Disposal Group, Held-for-sale, Not Discontinued Operations
Assets and Liabilities Held for Sale [Line Items]
Accounts receivable, net - assets held for sale	6,837
Other assets held for sale	3,113
Property, Plant and Equipment - assets held for sale	56
Goodwill - assets held for sale	3,033
Allowance for reduction of assets held for sale	(4,700)
Total assets held for sale	9,163
Accounts payable held for sale	2,845
Accrued employee compensation and benefits	943
Total liabilities held for sale	3,788
Business Unit From Customer Growth Services And Customer Strategy Services Segments | Disposal Group, Held-for-sale, Not Discontinued Operations | Customer Relationships [Member]
Assets and Liabilities Held for Sale [Line Items]
Intangible assets held for sale	$ 824