PROPERTY AND EQUIPMENT (Tables)

12 Months Ended

Dec. 31, 2017

Property Plant And Equipment [Abstract]

Summarizes Components of Property and Equipment, Net

Property and equipment are recorded at historical cost, net of accumulated depreciation. The following table summarizes components of property and equipment, net for each of the periods indicated:

	As of December 31,
	2017			2016
	(in thousands)
Land	$	4,158		$	4,158
Building and improvements		14,543			12,729
Software and computer equipment		8,965			6,775
Lab equipment		9,860			14,149
Office equipment		2,211			3,028
Leasehold improvements		13,633			22,872
Construction in progress		7,808			4,436
Property and equipment, gross		61,178			68,147
Less: accumulated depreciation		(18,022	)		(30,346	)
Property and equipment, net	$	43,156		$	37,801