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Collaboration Agreement with GSK - Additional Information (Details) $ in Thousands				1 Months Ended		3 Months Ended		6 Months Ended
	Jul. 06, 2026	Aug. 17, 2021 USD ($)	Jul. 01, 2021 USD ($)	May 31, 2023 USD ($)	Jan. 31, 2022 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development expense						$ 19,460	$ 27,611	$ 37,317	$ 61,252
Subsequent Event
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Agreement termination date	Jan. 02, 2027
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						3,300	7,900	$ 4,400	11,500
Deferred revenue						162,900		162,900		$ 171,200
Research and development expense						300	$ 6,100	1,500	$ 10,400
Transaction price						564,000		564,000
Contract with customer, refund liability						0		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		$ 1,500,000
Alector
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage Of Development Cost								0.40

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