Significant Accounting Policies - Summary of Effect of the Adoption of ASC 842 on Statement of Operations and Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Operating expenses:
Research and development	$ 11,791	$ 16,774	$ 44,096	$ 78,462
Other income (expense):
Interest expense	(1,471)	(1,078)	(4,285)	(2,493)
Net loss	(117,087)	(26,527)	(159,307)	(110,936)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	$ 300	$ 300	1,005	810
Non-cash lease expense			908	1,031
Changes in operating assets and liabilities:
Accrued expenses and other current liabilities				(8,576)
Cash flows from financing activities
Other			$ (253)	(709)
Supplemental disclosure of noncash investing and financing activities:
Right-of-use assets obtained in exchange for lease liabilities				$ 23,035
Accounting Standards Update [Extensible Enumeration]		Accounting Standards Update 2016-02 [Member]		Accounting Standards Update 2016-02 [Member]
Previously ASC 842
Operating expenses:
Research and development		$ 16,391		$ 77,308
Other income (expense):
Interest expense		(1,241)		(3,002)
Net loss		(26,307)		(110,291)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense				808
Changes in operating assets and liabilities:
Accrued expenses and other current liabilities				(7,753)
Cash flows from financing activities
Other				(1,144)
ASC 842 Adjustments
Operating expenses:
Research and development		383		1,154
Other income (expense):
Interest expense		163		509
Net loss		$ (220)		(645)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense				2
Non-cash lease expense				1,031
Changes in operating assets and liabilities:
Accrued expenses and other current liabilities				(823)
Cash flows from financing activities
Other				435
Supplemental disclosure of noncash investing and financing activities:
Right-of-use assets obtained in exchange for lease liabilities				$ 23,035