Balance Sheet Account Details (Property Plant and Equipment) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 25,834	$ 28,796
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	9,796	10,407
Property, Plant and Equipment, Net	16,038	18,389
Lab Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	6,752	9,665
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	2,549	2,598
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	1,296	1,296
Software and Software Development Costs [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	733	733
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 14,504	$ 14,504