Property and Equipment (Details 1) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment
Property, Plant and Equipment, Gross	$ 76,310	$ 79,265
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(58,623)	(59,875)
Property, Plant and Equipment, Net	17,687	19,390
Computers and Software
Property, Plant and Equipment
Property, Plant and Equipment, Gross	4,605	7,667
Furniture and Fixtures
Property, Plant and Equipment
Property, Plant and Equipment, Gross	6,006	6,003
Laboratory Equipment
Property, Plant and Equipment
Property, Plant and Equipment, Gross	3,423	3,423
Leasehold Improvements
Property, Plant and Equipment
Property, Plant and Equipment, Gross	400	296
Buildings
Property, Plant and Equipment
Property, Plant and Equipment, Gross	59,212	59,212
Land
Property, Plant and Equipment
Property, Plant and Equipment, Gross	$ 2,664	$ 2,664