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Collaboration and License Agreements and Supply Agreements - Additional Information (Details) | 1 Months Ended | 3 Months Ended | 12 Months Ended |
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Jun. 30, 2022 USD ($) Program PerformanceObligation | Mar. 31, 2020 USD ($) | May 31, 2019 USD ($) | Jul. 31, 2018 USD ($) Program | Aug. 31, 2017 Program | Mar. 31, 2023 USD ($) Installment | Mar. 31, 2022 USD ($) | 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 |  |
Vaxcyte, Inc. |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  | 17,500,000 |  | 17,500,000 |  |
Nonrefundable, non-creditable upfront payment receivable |  |  |  |  |  |  |  | $ 10,000,000.0 |  |
Shares received | shares |  |  |  |  |  |  |  | 167,780 |  |
Common stock fair value |  |  |  |  |  |  |  | $ 7,500,000 |  |
Additional nonrefundable and noncreditable payment |  |  |  |  |  | 5,000,000.0 |  |  |  |
Regulatory milestones cash in payment |  |  |  |  |  | $ 75,000,000.0 |  |  |  |
Number of installments | Installment |  |  |  |  |  | 2 |  |  |  |
Additional milestone payment |  |  |  |  |  | $ 60,000,000.0 |  |  |  |
BMS Agreement |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Number of programs advancing through preclinical development | Program |  |  |  |  | 4 |  |  |  |  |
Contingent payments |  |  | $ 275,000,000.0 |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  | 0 |  | 0 |  |
2018 BMS Master Services Agreement |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  | 1,200,000 |  | 3,100,000 |  |
2018 Merck Agreement |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  | $ 0 |  | 0 |  |
Milestone payment receivable upon initiation of IND enabling toxicology study |  |  |  |  |  |  |  |  |  | $ 15,000,000.0
2018 Merck Agreement | Merck Sharp & Dohme Corp |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Number of target programs | Program |  |  |  | 2 |  |  |  |  |  |
Initial transaction price |  |  |  | $ 60,000,000.0 |  |  |  |  |  |
Contingent payment received |  |  |  |  |  |  |  | 10,000,000.0 |  |
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 |  | $ 5,000,000.0 |  |  |  |  |  |  |  |
Extended research term |  | 1 year |  |  |  |  |  |  |  |
2020 Merck Master Services Agreement |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  | $ 0 |  | 0 |  |
MDA Agreement | EMD Serono |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  | 0 |  | 0 |  |
Supply Agreement | Vaxcyte, Inc. |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Reimbursements expenses accruals |  |  |  |  |  | 5,300,000 |  | 4,800,000 |  |
Reimbursements expenses |  |  |  |  |  | 1,900,000 | $ 2,400,000 |  |  |
Astellas License and Collaboration Agreement |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Deferred revenue |  |  |  |  |  | 83,500,000 |  | 86,100,000 |  |
Number of target programs | Program | 3 |  |  |  |  |  |  |  |  |
Upfront payment received |  |  |  |  |  | 90,000,000.0 |  |  |  |
Transaction price | $ 90,000,000.0 |  |  |  |  |  |  |  |  |
Estimated service period | 4 years |  |  |  |  |  |  |  |  |
Recognition of up front payment | $ 89,100,000 |  |  |  |  |  |  |  |  |
Upfront payment revenue not recognized |  |  |  |  |  | 32,600,000 |  |  |  |
Nonrefundable, non-creditable upfront payment receivable |  |  |  |  |  |  |  | $ 90,000,000.0 |  |
Number of performance obligations | PerformanceObligation | 4 |  |  |  |  |  |  |  |  |
Maximum amount eligible to receive for development, regulatory and commercial milestones for each product candidate |  |  |  |  |  | $ 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 |  |  |  |  |  |  |  |  |

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