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Collaboration and License Agreements and Supply Agreements - Additional Information (Details) | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended |
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Oct. 31, 2023 USD ($) | Jun. 30, 2023 USD ($) | Jun. 30, 2022 USD ($) PerformanceObligation Program | Apr. 30, 2022 USD ($) | Dec. 31, 2021 USD ($) | Mar. 31, 2020 USD ($) | Jul. 31, 2018 USD ($) Program | Aug. 31, 2017 Program | Sep. 30, 2023 USD ($) Installment | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) Installment | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($) shares | Dec. 31, 2021 USD ($) | Apr. 30, 2021 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accounts receivable, reserve for credit losses |  |  |  |  |  |  |  |  | $ 0 |  | $ 0 |  | $ 0 |  |
Vaxcyte, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  |  |  |  | 22,500,000 |  | 22,500,000 |  | 17,500,000 |  |
Nonrefundable, non-creditable upfront payment receivable |  |  |  |  |  |  |  |  |  |  |  |  | $ 10,000,000 |  |
Shares received | shares |  |  |  |  |  |  |  |  |  |  |  |  | 167,780 |  |
Common stock fair value |  |  |  |  |  |  |  |  |  |  |  |  | $ 7,500,000 |  |
Payment received from definitive agreement | $ 5,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory milestones cash in payment |  |  |  |  |  |  |  |  | $ 75,000,000 |  | $ 75,000,000 |  |  |  |
Number of installments | Installment |  |  |  |  |  |  |  |  | 2 |  | 2 |  |  |  |
Additional milestone payment |  |  |  |  |  |  |  |  | $ 60,000,000 |  | $ 60,000,000 |  |  |  |
Blackstone Life Sciences |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment received |  | $ 140,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
BMS Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of programs advancing through preclinical development | Program |  |  |  |  |  |  |  | 4 |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |  |
2018 BMS Master Services Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 3,100,000 |  |
2015 License Agreement | Blackstone Life Sciences | Royalty |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment received |  | $ 140,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue interest percentage |  | 4.00% |  |  |  |  |  |  |  |  |  |  |  |  |
2018 Merck Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  |  |  |  | 0 |  | $ 0 |  | 0 |  |
Milestone payment receivable upon initiation of IND enabling toxicology study |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 15,000,000
2018 Merck Agreement | Merck Sharp & Dohme Corp |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of target programs | Program |  |  |  |  |  |  | 2 |  |  |  |  |  |  |  |
Initial transaction price |  |  |  |  |  |  | $ 60,000,000 |  |  |  |  |  |  |  |
Contingent payment received |  |  |  |  |  |  |  |  |  |  |  |  | 10,000,000 |  |
Milestone payment received |  |  |  |  |  |  |  |  |  |  |  |  | 2,500,000 |  |
Additional milestone payment received |  |  |  |  |  |  |  |  |  |  |  |  | 7,500,000 |  |
Revenue recognition aggregate contingent payments eligible to receive |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 500,000,000 |
Milestone method revenue recognition description |  |  |  |  |  |  |  |  |  |  | If one or more products from the target program is developed for non-oncology or a single indication, the Company will be eligible for reduced aggregate contingent payments. In addition, the Company is eligible to receive tiered royalties ranging from mid-single digit to low teen percentages on the worldwide sales of any commercial products that may result from the collaboration. |  |  |  |
First Cytokine-Derivative Program | Merck Sharp & Dohme Corp |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment received |  |  |  |  |  | $ 5,000,000 |  |  |  |  |  |  |  |  |
Extended research term |  |  |  |  |  | 1 year |  |  |  |  |  |  |  |  |
2020 Merck Master Services Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  |  |  |  | 0 |  | $ 0 |  | 0 |  |
MDA Agreement | EMD Serono |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |  |
Supply Agreement | Vaxcyte, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reimbursements expenses accruals |  |  |  |  |  |  |  |  | 6,100,000 |  | 6,100,000 |  | 4,800,000 |  |
Reimbursements expenses |  |  |  |  |  |  |  |  | 2,800,000 | $ 4,000,000 | 5,600,000 | $ 10,200,000 |  |  |
Astellas License and Collaboration Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  |  |  |  | 74,600,000 |  | 74,600,000 |  | 86,100,000 |  |
Number of target programs | Program |  |  | 3 |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment received |  |  |  |  |  |  |  |  |  |  | 90,000,000 |  |  |  |
Transaction price |  |  | $ 90,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Estimated service period |  |  | 4 years |  |  |  |  |  |  |  |  |  |  |  |
Recognition of up front payment |  |  | $ 89,100,000 |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment revenue not recognized |  |  |  |  |  |  |  |  |  |  | 32,300,000 |  |  |  |
Nonrefundable, non-creditable upfront payment receivable |  |  |  |  |  |  |  |  |  |  |  |  | 90,000,000 |  |
Number of performance obligations | PerformanceObligation |  |  | 4 |  |  |  |  |  |  |  |  |  |  |  |
Maximum amount eligible to receive for development, regulatory and commercial milestones for each product candidate |  |  |  |  |  |  |  |  | 422,500,000 |  | 422,500,000 |  |  |  |
Astellas License and Collaboration Agreement | Future Services on Collaboration Joint Steering Committee ("JSC") |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recognition of up front payment |  |  | $ 900,000 |  |  |  |  |  |  |  |  |  |  |  |
Tasly License Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nonrefundable upfront payment receivable |  |  |  |  | $ 40,000,000 |  |  |  |  |  |  |  |  | 40,000,000 |
Maximum potential payments related to development regulatory commercialization contingent payments and milestones |  |  |  | $ 350,000,000 | $ 345,000,000 |  |  |  |  |  |  |  |  | $ 345,000,000 |
Minimum term of royalties receivable based on annual net sales |  |  |  |  | 10 years |  |  |  |  |  |  |  |  |  |
Reduction of research and development expenses recognized |  |  |  |  |  |  |  |  | 16,000 | $ 0 | $ 16,000 | $ 0 |  |  |
Initial licensing payment due |  |  |  | 25,000,000 |  |  |  |  |  |  |  |  |  |  |
Initial licensing payment in escrow |  |  |  | $ 15,000,000 |  |  |  |  |  |  |  |  |  |  |
Upfront payment revenue recognized |  |  |  |  |  |  |  |  |  |  |  |  | 25,000,000 |  |
Upfront payment withholding tax amount |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,500,000 |  |
Revenue recognized from contingent payment |  |  |  |  |  |  |  |  | 5,000,000 |  |  |  |  |  |
Income tax charge related to contingent payment |  |  |  |  |  |  |  |  | 500,000 |  |  |  |  |  |
Maximum refund period on termination of study |  |  |  |  |  |  |  |  |  |  | 30 days |  |  |  |
Contingent payment recognized as deferred revenue |  |  |  |  |  |  |  |  | 5,000,000 |  |  |  |  |  |
Withholding tax on deferred revenue |  |  |  |  |  |  |  |  | $ 500,000 |  |  |  |  |  |

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