DEBT - Components of Interest Expense (Detail) - 2016 Convertible Senior Notes - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Debt Instrument [Line Items]
Amortization of the discount on the liability component	$ 1,885	$ 1,766	$ 3,744	$ 3,433
Cash interest related to the contractual interest coupon	824	837	1,669	1,639
Total	$ 2,709	$ 2,603	$ 5,413	$ 5,072