v3.25.2
Collaboration Agreements - Summary of Activity and Reimbursement Amounts Related to Collaboration Agreement (Detail) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Dec. 31, 2020
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]          
Revenue $ 31,660 $ 8,654 $ 45,724 $ 16,556  
Research and development expenses 23,917 62,564 46,676 134,297  
Selling, general and administrative expenses 61,997 55,983 119,589 108,556  
Collaboration Revenue - Related Party [Member]          
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]          
Revenue 23,209 7,420 37,036 13,633  
Biogen Collaboration Agreement [Member]          
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]          
Revenue         $ 1,100,000
Cost of revenues 5 1,294 730 2,495  
Research and development expenses 738 4,943 2,034 11,974  
Selling, general and administrative expenses 22,826 13,072 43,420 26,055  
Reimbursement amounts to (from) collaboration [Abstract]          
Collaboration revenue - related party (23,209) (7,420) (37,036) (13,633)  
Cost of revenues (697) (566) (827) (1,128)  
Selling, general and administrative expenses 6,231 1,019 11,017 3,325  
Biogen Collaboration Agreement [Member] | Research and Development [Member]          
Reimbursement amounts to (from) collaboration [Abstract]          
Research and development expenses 2,975 (3,325) 2,736 (8,982)  
Biogen Collaboration Agreement [Member] | Collaboration Revenue - Related Party [Member]          
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]          
Revenue $ 23,209 $ 7,420 $ 37,036 $ 13,633