EQUITY-BASED COMPENSATION PLANS (NARRATIVE) (DETAILS) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense	$ 3,300,000	$ 3,400,000	$ 9,842,000	$ 10,310,000
Non-option Equity Awards Granted			755,835	637,042
Stock Options [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense	100,000	100,000	300,000	400,000
Unrecognized Compensation Expense	400,000		400,000
Restricted Stock Units (RSUs) [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense	3,100,000	3,300,000	9,400,000	9,900,000
Unrecognized Compensation Expense	28,600,000		28,600,000
Cost of Services [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense	600,000	500,000	1,600,000	1,500,000
Selling General And Administrative Expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense	$ 2,700,000	$ 2,900,000	$ 8,300,000	$ 8,800,000