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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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