COMPONENTS OF FIXED ASSETS (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Laboratory equipment	$ 4,504	$ 4,134
Furniture and office equipment	1,075	944
Software and computers	3,897	3,071
Leasehold improvements	4,554	4,554
Total	14,030	12,703
Less: accumulated depreciation	(8,817)	(8,072)
Property, plant and equipment, Net	$ 5,213	$ 4,631