STOCK BASED COMPENSATION - Expense Resulting from Stock Option Awards and ESPP (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 4,145	$ 4,129	$ 12,088	$ 12,346
Stock Options | Cost of revenues
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	32	34	102	105
Stock Options | Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	3,561	3,421	10,265	10,329
Restricted Stock Units | Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	389	389	967	1,077
Employee Stock Purchase Plan (ESPP) | Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 163	$ 285	$ 754	$ 835