Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity - USD ($) $ in Thousands	Total	At The Market Offering	Follow On Public Offering	Sutro Stock Payment	Common Stock	Common Stock At The Market Offering	Common Stock Follow On Public Offering	Common Stock Sutro Stock Payment	Additional Paid-in Capital	Additional Paid-in Capital At The Market Offering	Additional Paid-in Capital Follow On Public Offering	Additional Paid-in Capital Sutro Stock Payment	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2020	$ 345,843				$ 54				$ 544,353				$ (198,564)
Beginning balance, shares at Dec. 31, 2020					51,071,593
Issuance of common stock upon initial public offering or at-the-market offering, net of issuance costs		$ 13,847				$ 1				$ 13,846
Common stock shares sold						567,045
Issuance of common stock under Employee Stock Purchase Plan	888								888
Issuance of common stock under Employee Stock Purchase Plan (in shares)					62,546
Release of restricted stock units	0
Exercise of stock options	3,012								3,012
Exercise of stock options (in shares)					931,114
Issuance of common stock to LonzaLtd.	10,001				$ 1				10,000
Issuance of common stock to Lonza Ltd. (in shares)					399,680
Unrealized losses on investment	(241)													$ (241)
Vesting of early exercised stock options	16								16
Stock-based compensation expense	10,729								10,729
Cumulative translation adjustment	0
Net Income (Loss)	(100,077)												(100,077)
Ending balance at Dec. 31, 2021	284,018				$ 56				582,844				(298,641)	(241)
Ending balance, shares at Dec. 31, 2021					53,031,978
Issuance of common stock upon initial public offering or at-the-market offering, net of issuance costs		97,299	$ 759,181	$ 7,995		$ 4	$ 21			97,295	$ 759,160	$ 7,995
Common stock shares sold						3,921,528	21,062,500	167,780
Issuance of common stock under Employee Stock Purchase Plan	1,033								1,033
Issuance of common stock under Employee Stock Purchase Plan (in shares)					61,709
Release of restricted stock units	(861)								(861)
Release of restricted stock units, shares					46,603
Exercise of stock options	4,895				$ 1				4,894
Exercise of stock options (in shares)					1,178,572
Unrealized losses on investment	(120)													(120)
Vesting of early exercised stock options	8								8
Stock-based compensation expense	23,650								23,650
Cumulative translation adjustment	0
Net Income (Loss)	(223,485)												(223,485)
Ending balance at Dec. 31, 2022	953,613				$ 82				1,476,018				(522,126)	(361)
Ending balance, shares at Dec. 31, 2022					79,470,670
Issuance of common stock upon initial public offering or at-the-market offering, net of issuance costs		$ 90,741	$ 545,302			$ 2	$ 13			$ 90,739	$ 545,289
Common stock shares sold						2,095,943	13,030,000
Issuance of common stock under Employee Stock Purchase Plan	2,038								2,038
Issuance of common stock under Employee Stock Purchase Plan (in shares)					76,275
Release of restricted stock units	(3,876)								(3,876)
Release of restricted stock units, shares					154,135
Exercise of stock options	5,608				$ 1				5,607
Exercise of stock options (in shares)					537,808
Unrealized losses on investment	538													538
Vesting of early exercised stock options	8								8
Stock-based compensation expense	48,760								48,760
Cumulative translation adjustment	2													2
Net Income (Loss)	(402,266)												(402,266)
Ending balance at Dec. 31, 2023	$ 1,240,468				$ 98				$ 2,164,583				$ (924,392)	$ 179
Ending balance, shares at Dec. 31, 2023					95,364,831