ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (INCOME STATEMENT CLASSIFICATION TABLE) (DETAILS) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Presentation of Income Statement Reclassifications [Line Items]
Revenue	$ 309,195	$ 305,900	$ 944,939	$ 903,611
Interest expense	2,337	1,646	5,711	5,197
Provision for income taxes	1,192	5,778	13,438	14,071
Net Income (Loss)	12,438	14,689	47,966	54,122
Accumulated Other Comprehensive Income (Loss)
Presentation of Income Statement Reclassifications [Line Items]
Net Income (Loss) - Other			5,280	2,949
Derivative Valuation, Net of Tax
Presentation of Income Statement Reclassifications [Line Items]
Net Income (Loss) - Other			4,601	2,186
Tax effect
Presentation of Income Statement Reclassifications [Line Items]
Provision for income taxes - Other	25	16	76	48
Net Income (Loss) - Other	(227)	(254)	(679)	(763)
Cost of Services | Tax effect
Presentation of Income Statement Reclassifications [Line Items]
Cost of services	(252)	(270)	(755)	(811)
Reclassification from accumulated other comprehensive income | Derivative Valuation, Net of Tax
Presentation of Income Statement Reclassifications [Line Items]
Provision for income taxes			4,382	1,399
Net Income (Loss)	(2,160)	(12)	(4,601)	(2,186)
Reclassification from accumulated other comprehensive income | Tax effect
Presentation of Income Statement Reclassifications [Line Items]
Provision for income taxes	2,091	7
Foreign Exchange Forward | Reclassification from accumulated other comprehensive income | Foreign Currency Translation Adjustment
Presentation of Income Statement Reclassifications [Line Items]
Revenue	(3,987)	248
Foreign Exchange Forward | Reclassification from accumulated other comprehensive income | Derivative Valuation, Net of Tax
Presentation of Income Statement Reclassifications [Line Items]
Revenue			(8,200)	(2,795)
Interest Rate | Reclassification from accumulated other comprehensive income | Derivative Valuation, Net of Tax
Presentation of Income Statement Reclassifications [Line Items]
Interest expense			$ (783)	$ (790)
Interest Rate | Reclassification from accumulated other comprehensive income | Loss on interest rate swaps [Member]
Presentation of Income Statement Reclassifications [Line Items]
Interest expense	$ (264)	$ (267)