Fair Value of Financial Instruments - Summary of Financial Instruments Measured at Fair Value on Recurring Basis (Details) - Fair Value Recurring - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets:
Total assets measured at fair value	$ 44,699	$ 71,783
Commercial Paper
Assets:
Short-term investments	27,987	27,136
Corporate Debt Securities
Assets:
Short-term investments	1,404	26,506
U.S. Government and Agency Securities
Assets:
Short-term investments	15,308	18,141
Significant Other Observable Inputs (Level 2)
Assets:
Total assets measured at fair value	44,699	71,783
Significant Other Observable Inputs (Level 2) | Commercial Paper
Assets:
Short-term investments	27,987	27,136
Significant Other Observable Inputs (Level 2) | Corporate Debt Securities
Assets:
Short-term investments	1,404	26,506
Significant Other Observable Inputs (Level 2) | U.S. Government and Agency Securities
Assets:
Short-term investments	$ 15,308	$ 18,141