Accrued Liabilities and Other Long-Term Liabilities - Summary of Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Accrued Liabilities and Other Liabilities [Abstract]
Accrued compensation and benefits	$ 3,069	$ 4,542
Accrued research and development expenses	4,028	3,274
Other accrued liabilities	951	1,675
Deferred rent	120	85
Total accrued liabilities	$ 8,168	$ 9,576	[1]

[1] The condensed balance sheet as of December 31, 2020 has been derived from the audited financial statements as of that date.