Related Party Transactions (Details) - USD ($) $ in Thousands			1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 29, 2026	Jul. 20, 2026	Nov. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Related Party Transaction [Line Items]
Research and development				$ 68,417	$ 50,627	$ 174,804	$ 145,486
Other long-term liabilities				1,515		1,515		$ 15,433
Accounts receivable				8,821		8,821		1,307
Deferred revenue, non-current, related party				24,594		24,594		49,138
Deferred revenue, current				0		0		7,123
Gross proceeds from private investment in public entity		$ 240,000
Convertible Debt | Roche Convertible Note
Related Party Transaction [Line Items]
Aggregate principal amount			$ 75,000
Accrued interest		2,500
Unamortized discount and debt issuance costs		$ 8,900
Shares upon conversion (in shares)		6,460,616
Carrying value		$ 68,600
Total interest expense				800		7,300
Coupon interest expense				200		2,100
Roche License and Option Agreement and Roche Promissory Note Agreement
Related Party Transaction [Line Items]
Proceeds from related party transaction			$ 75,000
Related Party
Related Party Transaction [Line Items]
Related party transaction amount				0	300	0	300
Other long-term liabilities				1,140		1,140
Accounts receivable				8,000		8,000
Deferred revenue, non-current, related party				24,594		24,594
Related Party | Material Transfer Agreements
Related Party Transaction [Line Items]
Research and development				1,900	$ 600	3,700	$ 1,300
Related Party | Roche License and Option Agreement and Roche Promissory Note Agreement | Convertible Debt | Roche Convertible Note
Related Party Transaction [Line Items]
Unamortized discount and debt issuance costs		$ 8,900
Shares upon conversion (in shares)		6,460,616
Carrying value		$ 68,600
Related Party | Roche License and Option Agreement
Related Party Transaction [Line Items]
Research and development	$ 3,400
Other long-term liabilities				15,000		15,000		$ 15,000
Accounts receivable	8,000
Contract asset	$ 600
Deferred revenue, non-current, related party				24,600		24,600
Deferred revenue, current				1,200		1,200
Related Party | Roche License and Option Agreement | Convertible Debt | Roche Convertible Note
Related Party Transaction [Line Items]
Accrued interest		$ 2,500
Total interest expense				800		7,300
Coupon interest expense				200		2,100
Related Party | SBX Evaluation
Related Party Transaction [Line Items]
Other long-term liabilities				1,100		1,100
Deferred revenue, current				$ 1,200		$ 1,200
Related Party | PIPE Financing | Perceptive Advisors, LLC
Related Party Transaction [Line Items]
Shares issued in PIPE financing (in shares)						5,500,000
Gross proceeds from private investment in public entity						$ 55,000
Related Party | PIPE Financing | RA Capital
Related Party Transaction [Line Items]
Shares issued in PIPE financing (in shares)						5,255,376
Gross proceeds from private investment in public entity						$ 52,600