Fair Value of Financial Instruments - Summary of Financial Instruments Measured at Fair Value on Recurring Basis (Details) - Fair Value Recurring - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets:
Total assets measured at fair value	$ 71,783	$ 39,983
Liabilities:
Preferred stock warrant liability		184
Commercial Paper
Assets:
Short-term investments	27,136	9,694
Corporate Debt Securities
Assets:
Short-term investments	26,506	24,781
U.S. Government and Agency Securities
Assets:
Short-term investments	18,141
Asset Backed Securities
Assets:
Short-term investments		5,508
Significant Other Observable Inputs (Level 2)
Assets:
Total assets measured at fair value	71,783	39,983
Significant Other Observable Inputs (Level 2) | Commercial Paper
Assets:
Short-term investments	27,136	9,694
Significant Other Observable Inputs (Level 2) | Corporate Debt Securities
Assets:
Short-term investments	26,506	24,781
Significant Other Observable Inputs (Level 2) | U.S. Government and Agency Securities
Assets:
Short-term investments	$ 18,141
Significant Other Observable Inputs (Level 2) | Asset Backed Securities
Assets:
Short-term investments		5,508
Significant Observable Inputs (Level 3)
Liabilities:
Preferred stock warrant liability		$ 184