EQUITY-BASED COMPENSATION (Schedule of Equity-based Compensation Expense for Restricted Stock Awards and Non-Qualified Stock Options) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense	$ 1,929	$ 1,622	$ 6,113	$ 5,209
Income tax benefits	(675)	(568)	(2,140)	(1,823)
Total equity-based compensation expense, net of tax	1,254	1,054	3,973	3,386
Cost of revenues [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense	103	60	370	128
Selling and marketing [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense	270	137	1,054	683
Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense	138	112	414	437
General and administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense	$ 1,418	$ 1,313	$ 4,275	$ 3,961