ACCUMULATED OTHER COMPREHENSIVE LOSS Reclassification (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of services	$ 58,152	$ 55,562	$ 115,688	$ 110,554
Selling, general and administrative expenses	8,582	7,301	16,643	15,549
Reclassification to operations	459	711	1,081	2,026
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	424	669	1,001	1,892
Selling, general and administrative expenses	$ 35	$ 42	$ 80	$ 134