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Collaboration Agreement with GSK - Additional Information (Details) $ in Thousands			1 Months Ended		3 Months Ended
	Aug. 17, 2021 USD ($)	Jul. 01, 2021 USD ($)	May 31, 2023 USD ($)	Jan. 31, 2022 USD ($)	Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development expense					$ 17,857	$ 33,641
GlaxoSmithKline plc
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Effective date of agreement	Aug. 17, 2021
Upfront payments		$ 700,000			$ 700,000
Milestone payment received	$ 500,000			$ 200,000
Percentage Of Development Cost					0.60
Collaboration revenue					$ 1,000	3,700
Deferred revenue					169,600		$ 171,200
Research and development expense					1,800	$ 4,300
Transaction price					568,000
Contract with customer, refund liability					0		$ 11,400
Maximum funding			$ 140,500
GlaxoSmithKline plc | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Additional milestone payments related to initiation of certain clinical studies and regulatory approval					$ 1,500,000
Alector
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage Of Development Cost					0.40

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