ACCUMULATED OTHER COMPREHENSIVE LOSS Reclassification (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of services	$ 69,597	$ 52,393	$ 185,284	$ 162,946
Selling, general and administrative expenses	9,335	7,503	25,981	23,052
Reclassification to operations	744	341	1,825	2,367
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges | Foreign exchange contracts | Amount Reclassified from Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of services	682	324	1,682	2,215
Selling, general and administrative expenses	$ 62	$ 17	$ 143	$ 152