Property and Equipment, Net

12 Months Ended

Dec. 31, 2016

Property Plant And Equipment [Abstract]

10. Property and Equipment, Net

Property and equipment, net as of December 31, 2016 and 2015 consisted of the following:

	December 31,
(in thousands)	2016			2015
Lab equipment	$	20,752		$	19,305
IT equipment		8,601			7,742
Leasehold improvements		21,153			21,026
Furniture and fixtures		959			910
Construction in process		515			2,243
Total property and equipment, gross		51,980			51,226
Less: Accumulated depreciation		(36,215	)		(29,311	)
Total property and equipment, net	$	15,765		$	21,915

Depreciation expense was $7.3 million, $5.5 million and $4.2 million for the years ended December 31, 2016, 2015 and 2014, respectively. Capitalized interest costs were insignificant for the years ended December 31, 2016, 2015 and 2014.

During the year ended December 31, 2016, the Company recognized a $0.5 million charge related to the disposal of property and equipment. There were no significant losses recognized related to the disposal of property and equipment during the years ended December 31, 2015 or 2014.