Collaboration Agreements - Schedule of Cost Sharing Payments and Reimbursements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Net cost sharing payments (reimbursements)	$ 9,202	$ 10,806	$ 5,513
Accounts payable	3,330	11,137
Takeda Pharmaceutical Company Limited
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Net cost sharing payments (reimbursements)	(6,603)	(5,936)	(12,165)
Takeda Pharmaceutical Company Limited | Collaborative Arrangement, PTV:PGRN
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Net cost sharing payments (reimbursements)	(6,456)	(4,789)	(7,065)
Takeda Pharmaceutical Company Limited | ATV:TREM2 Collaboration Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Net cost sharing payments (reimbursements)	(147)	(1,147)	(5,100)
Takeda Pharmaceutical Company Limited | Collaborative Arrangement, PTV:PGRN And ATV:TREM2
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Receivable	1,600	1,500
Biogen | LRRK2 Program License
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Net cost sharing payments (reimbursements)	15,805	16,742	$ 17,678
Biogen | Biogen Collaboration Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Accounts payable	$ 2,800	$ 2,500