ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (INCOME STATEMENT CLASSIFICATION TABLE) (DETAILS) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Presentation of Income Statement Reclassifications [Line Items]
Sales Revenue Services Net	$ 312,796	$ 309,195	$ 930,311	$ 944,939
Interest Expense.	2,041	2,337	5,758	5,711
Benefit from (provision for) income taxes	813	(1,192)	(6,667)	(13,438)
Net income	12,649	12,438	37,096	47,966
Accumulated Other Comprehensive Income (Loss)
Presentation of Income Statement Reclassifications [Line Items]
Net Income (Loss) - Other			12,317	(5,280)
Derivative Valuation, Net of Tax
Presentation of Income Statement Reclassifications [Line Items]
Net Income (Loss) - Other			11,189	(4,601)
Reclassification from accumulated other comprehensive income
Presentation of Income Statement Reclassifications [Line Items]
Net income	(4,179)	(2,160)
Net Income (Loss) - Other	(724)	(227)	(1,128)	(679)
Reclassification from accumulated other comprehensive income | Derivative Valuation, Net of Tax
Presentation of Income Statement Reclassifications [Line Items]
Net income			(11,189)	(4,601)
Reclassification from accumulated other comprehensive income | Tax effect
Presentation of Income Statement Reclassifications [Line Items]
Benefit from (provision for) income taxes	3,028	2,091	8,106	4,382
Provision for income taxes - Other	80	25	124	76
Reclassification from accumulated other comprehensive income | Cost of Services
Presentation of Income Statement Reclassifications [Line Items]
Cost of services	(804)	(252)	(1,252)	(755)
Foreign Exchange Forward | Reclassification from accumulated other comprehensive income | Foreign Currency Translation Adjustment
Presentation of Income Statement Reclassifications [Line Items]
Sales Revenue Services Net	(7,103)	(3,987)	(18,860)	(8,200)
Interest Rate | Reclassification from accumulated other comprehensive income | Loss on interest rate swaps [Member]
Presentation of Income Statement Reclassifications [Line Items]
Interest Expense.	$ (104)	$ (264)	$ (435)	$ (783)