STOCK BASED COMPENSATION - Expense Resulting from Stock Option Awards and ESPP (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 4,452	$ 3,896	$ 9,124	$ 7,943
Stock Options [Member] | Cost of revenues
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	21	30	28	70
Stock Options [Member] | Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	3,818	3,174	7,859	6,704
Restricted Stock Units (RSUs) [Member] | Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	314	383	629	578
ESPP shares [Member] | Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 299	$ 309	$ 608	$ 591