Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deferred Tax Assets:
Net operating loss carryforwards	$ 51,796	$ 12,510	$ 5,233
Operating lease right-of-use asset liability	5,686
Deferred revenue	2,857	5,719	5,125
Stock-based compensation	1,750	509	274
Intangible assets	1,195	609	804
Accruals and reserves	654	446	431
Research and development credit carryforwards	26	26	26
Gross deferred tax assets	63,964	19,819	11,893
Less: Valuation allowance	(57,715)	(19,815)	(11,739)
Deferred tax assets, net of valuation allowance	6,249	4	154
Deferred tax liabilities:
Fixed assets		$ (4)	$ (154)
Basis Difference IPR&D	(313)
Operating lease right-of-use asset	(6,061)
Net deferred tax liabilities	$ (125)