ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) Reclassification (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of services	$ 49,082	$ 45,522
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Foreign Exchange Contract [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of services	$ 401