SEGMENT INFORMATION (SEGMENT FINANCIALS) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net Revenue	$ 394,356	$ 375,249
Depreciation and amortization	16,743	17,924
Income (Loss) from Operations	32,092	24,941
Capital Expenditures	13,200	7,508
Total Assets	1,188,642		$ 1,054,508
Goodwill	205,180		204,633
Operating Segments
Segment Reporting Information [Line Items]
Net Revenue	394,544
Intersegment Eliminations
Segment Reporting Information [Line Items]
Net Revenue	(188)
Customer Strategy Services [Member]
Segment Reporting Information [Line Items]
Net Revenue	13,430	14,860
Depreciation and amortization	534	522
Income (Loss) from Operations	(1,228)	502
Capital Expenditures	422	124
Total Assets	68,658		60,755
Goodwill	24,328		24,179
Customer Strategy Services [Member] \| Operating Segments
Segment Reporting Information [Line Items]
Net Revenue	13,430	14,860
Customer Strategy Services [Member] \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Net Revenue	0
Customer Technology Services [Member]
Segment Reporting Information [Line Items]
Net Revenue	52,423	35,208
Depreciation and amortization	1,774	1,630
Income (Loss) from Operations	8,987	4,844
Capital Expenditures	3,319	31
Total Assets	164,216		162,222
Goodwill	42,006		41,979
Customer Technology Services [Member] \| Operating Segments
Segment Reporting Information [Line Items]
Net Revenue	52,611	35,208
Customer Technology Services [Member] \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Net Revenue	(188)
Customer Growth Services [Member]
Segment Reporting Information [Line Items]
Net Revenue	38,934	32,540
Depreciation and amortization	632	595
Income (Loss) from Operations	4,250	1,380
Total Assets	52,070		42,981
Goodwill	24,439		24,439
Customer Growth Services [Member] \| Operating Segments
Segment Reporting Information [Line Items]
Net Revenue	38,934	32,540
Customer Growth Services [Member] \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Net Revenue	0
Customer Management Services [Member]
Segment Reporting Information [Line Items]
Net Revenue	289,569	292,641
Depreciation and amortization	13,803	15,177
Income (Loss) from Operations	20,083	18,215
Capital Expenditures	9,459	7,353
Total Assets	903,698		788,550
Goodwill	114,407		$ 114,036
Customer Management Services [Member] \| Operating Segments
Segment Reporting Information [Line Items]
Net Revenue	289,569	$ 292,641
Customer Management Services [Member] \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Net Revenue	$ 0

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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