Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property and equipment, net
Total property and equipment	$ 38,046	$ 35,139
Accumulated depreciation and amortization	(31,234)	(28,033)
Property and equipment, net	6,812	7,106
Depreciation and amortization expense	3,941	3,747	$ 2,825
Computer Equipment and Software
Property and equipment, net
Total property and equipment	1,767	1,712
Office Equipment
Property and equipment, net
Total property and equipment	672	672
Laboratory Equipment
Property and equipment, net
Total property and equipment	22,079	19,948
Leasehold Improvements
Property and equipment, net
Total property and equipment	12,347	11,668
Construction in Progress
Property and equipment, net
Total property and equipment	$ 1,181	$ 1,139

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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