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Collaboration Agreements - Additional Information (Details) $ in Thousands			1 Months Ended					3 Months Ended		12 Months Ended
	Aug. 17, 2021 USD ($)	Jul. 01, 2021 USD ($)	May 31, 2023 USD ($)	Mar. 31, 2023 USD ($)	Jan. 31, 2022 USD ($)	Jan. 31, 2018 USD ($)	Oct. 31, 2017 USD ($)	Dec. 31, 2023 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Feb. 28, 2023 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development expense										$ 192,115	$ 210,418	$ 189,407
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										$ 66,600	62,900
Deferred revenue								$ 247,400		247,400	444,900
Research and development expense										21,800	14,700
Reduction in transaction price									$ 4,200
Transaction price								569,000		569,000
Contract with customer, refund liability			$ 128,400
Maximum funding			140,500
Cumulative adjustment to revenue			26,900					4,900
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
Transaction price		$ 700,000
GlaxoSmithKline plc | Minimum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Transaction price			$ 571,600
GlaxoSmithKline plc | Change in Estimate [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contract with customer, refund liability								106,500		$ 106,500
Alector
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage Of Development Cost										0.40
AbbVie Biotechnology Limited
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront payments							$ 205,000			$ 205,000
Milestone payment received				$ 17,800		$ 200,000	5,000		$ 5,700	17,800
Exclusive option rights exercised for each program							250,000
Additional milestone payments related to initiation of certain clinical studies and regulatory approval								6,800		6,800
Collaboration revenue										30,500	70,700	$ 14,900
Deferred revenue								46,400		46,400	$ 46,700
Payment for enrollment of additional patients								$ 12,500		12,500
AbbVie Biotechnology Limited | Deferred Revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue										$ 10,900
AbbVie Biotechnology Limited | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Additional milestone payments related to initiation of certain clinical studies and regulatory approval							$ 225,000						$ 12,500

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