PRINCIPAL CLIENTS (Details) - USD ($) $ in Thousands			3 Months Ended				6 Months Ended
	Jan. 04, 2014	Jul. 28, 2011	Jun. 30, 2015		Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014
T-Mobile USA, Inc., a subsidiary of Deutsche Telekom
Revenue, Major Customers [Line Items]
Revenue			$ 17,033		$ 18,785		$ 35,123	$ 37,424
Revenue concentration, percentage			26.80%		30.70%		27.60%	30.10%
Initial term of the master service agreement		5 years
Master services agreement, renewal term		1 year
Notice of termination option of the initial term		90 days
AT&T Services, Inc. and AT&T Mobility, LLC, subsidiaries of AT&T Inc.
Revenue, Major Customers [Line Items]
Revenue			$ 8,070	[1]	$ 13,753	[1]	$ 18,810	$ 29,097
Revenue concentration, percentage			12.70%	[1]	22.50%	[1]	14.80%	23.40%
Comcast Cable Communications Management LLC, subsidiary of Comcast Corporation
Revenue, Major Customers [Line Items]
Revenue			$ 7,930	[2]	$ 10,777	[2]	$ 16,809	$ 21,737
Revenue concentration, percentage			12.50%	[2]	17.60%	[2]	13.20%	17.50%
Initial term of the master service agreement	1 year
Master services agreement, renewal term	1 year
Notice of termination option of the initial term	90 days

[1] Revenue from this customer is generated through our Domestic and Offshore segments.

[2] Revenue from this customer is generated through our Domestic and Offshore segments in 2014 and 2015 and through our Nearshore segment in 2014.