Balance Sheet Details - Property Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Total property and equipment, gross	$ 2,027	$ 28,796
Accumulated depreciation and amortization	(1,743)	(10,407)
Total property and equipment, net	284	18,389
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Total property and equipment, gross	386	14,504
Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Total property and equipment, gross	598	2,598
Computer Equipment [Member]
Property Plant And Equipment [Line Items]
Total property and equipment, gross	310	1,296
Software and Software Development Costs [Member]
Property Plant And Equipment [Line Items]
Total property and equipment, gross	$ 733	733
Lab Equipment [Member]
Property Plant And Equipment [Line Items]
Total property and equipment, gross		$ 9,665