OPERATING SEGMENTS, Revenues by Service Offering (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Revenue from External Customer [Line Items]
Revenues	$ 174,695	$ 133,184	$ 335,079	$ 257,382
Software development
Revenue from External Customer [Line Items]
Revenues	119,852	90,298	230,539	174,078
Application testing services
Revenue from External Customer [Line Items]
Revenues	34,196	26,547	65,966	50,700
Application maintenance and support
Revenue from External Customer [Line Items]
Revenues	14,513	10,648	25,891	21,487
Infrastructure services
Revenue from External Customer [Line Items]
Revenues	3,484	3,461	7,238	6,871
Licensing
Revenue from External Customer [Line Items]
Revenues	978	720	1,806	1,298
Reimbursable expenses and other revenues
Revenue from External Customer [Line Items]
Revenues	$ 1,672	$ 1,510	$ 3,639	$ 2,948