Property and Equipment

12 Months Ended

Dec. 31, 2017

Property, Plant and Equipment [Abstract]

Property and Equipment

Property and Equipment

As of December 31, 2017 and 2016, property and equipment, net consists of the following (in thousands):

	2017			2016			Depreciable Lives
Computer equipment	$	3,061		$	2,991		3 years
Software	11,062			10,508			3 years
Office furniture and equipment	2,530			2,645			5 to 6 years
Laboratory equipment	51,315			47,938			7 years
Leasehold improvements	25,356			13,333			Shorter of asset life or lease term
Less: accumulated depreciation	(63,408		)	(56,568		)
	$	29,916		$	20,847

During 2017, the Company disposed of property and equipment with a gross carrying amount of $1.5 million and accumulated depreciation of $1.2 million. The Company did not dispose of any property and equipment during 2016. Depreciation and amortization expense amounted to $8.0 million, $7.6 million, and $7.6 million in the years ended December 31, 2017, 2016 and 2015, respectively.