Balance Sheet Components - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021		Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 49,759	$ 49,039
Less: accumulated depreciation and amortization	(40,323)	(38,968)
Total property and equipment, net	9,436	10,071	[1]	$ 22,300
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	25,880	25,880
Laboratory equipment and office furniture
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	22,227	21,916
Computer equipment
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	1,253	1,225
Construction-in-progress
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 399	$ 18

[1] The condensed consolidated balance sheet as of December 31, 2021 has been derived from the audited financial statements as of that date.