OPERATING SEGMENTS, Revenues by Service Offering (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Revenue from External Customer [Line Items]
Revenues	$ 192,764	$ 140,150	$ 527,843	$ 397,532
Software development
Revenue from External Customer [Line Items]
Revenues	134,000	93,870	364,539	267,948
Application testing services
Revenue from External Customer [Line Items]
Revenues	37,155	27,773	103,121	78,473
Application maintenance and support
Revenue from External Customer [Line Items]
Revenues	14,824	11,758	40,715	33,245
Infrastructure services
Revenue from External Customer [Line Items]
Revenues	3,502	3,754	10,740	10,625
Licensing
Revenue from External Customer [Line Items]
Revenues	820	809	2,626	2,107
Reimbursable expenses and other revenues
Revenue from External Customer [Line Items]
Revenues	$ 2,463	$ 2,186	$ 6,102	$ 5,134