INTANGIBLE ASSETS - Amortization (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Finite-Lived Intangible Assets [Line Items]
Total amortization expense	$ 3,910	$ 3,807	$ 7,795	$ 5,542
Research and development
Finite-Lived Intangible Assets [Line Items]
Total amortization expense	81	193	163	414
Selling, general and administrative
Finite-Lived Intangible Assets [Line Items]
Total amortization expense	$ 3,829	$ 3,614	$ 7,632	$ 5,128