Income Taxes - Schedule of Reconciliation of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Expected income tax benefit at federal statutory rate	$ (45,051)	$ (34,423)	$ (22,605)
State income tax benefit, net of federal benefit	(797)	(128)	(7,083)
Change in valuation allowance	59,951	39,733	34,495
R&D credit	(18,179)	(10,918)	(7,117)
Stock-based compensation	1,241	781	1,196
Australian tax incentive	35	266	27
State rate change	44	3,243	(8)
Uncertain tax positions	2,691	0	0
Other	65	1,446	1,095
Provision for income taxes	$ 0	$ 0	$ 0