Collaboration Agreements - Takeda (Details)		1 Months Ended	3 Months Ended		75 Months Ended
		Dec. 31, 2021 contract	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration revenue from customers	[1]		$ 0	$ 35,141,000
Takeda Collaboration Agreement | Takeda Pharmaceutical Company Limited
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Remaining performance obligation			0		$ 0
Collaborative Arrangement, PTV:PGRN and ATV:TREM2 | Takeda Pharmaceutical Company Limited
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of new contracts | contract		2
Collaborative Arrangement, PTV:PGRN and ATV:TREM2 | Takeda Pharmaceutical Company Limited | Prepaid Assets and Other Current Assets
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Receivable			1,900,000		1,900,000	$ 2,700,000
Collaborative Arrangement, PTV:PGRN and ATV:TREM2 | Takeda Pharmaceutical Company Limited | Milestone Payment
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration revenue from customers					10,000,000
Collaborative Arrangement, PTV:PGRN and ATV:TREM2 | Takeda Pharmaceutical Company Limited | Option Fee Payment
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration revenue from customers					10,000,000
Collaborative Arrangement, PTV:PGRN and ATV:TREM2 | Takeda Pharmaceutical Company Limited | Product
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration revenue from customers					$ 0
Collaborative Arrangement, PTV:PGRN | Takeda Pharmaceutical Company Limited
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Offset to research and development expense, cost reimbursement			1,200,000	1,500,000
Collaborative Arrangement, ATV:TREM2 | Takeda Pharmaceutical Company Limited
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Offset to research and development expense, cost reimbursement			$ 500,000	$ 1,700,000

[1] Includes related-party collaboration revenue from customers of $0.1 million for the three months ended March 31, 2023.