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License Agreements - Additional Information (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 12 Months Ended
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Dec. 31, 2022 | Mar. 31, 2022 | Aug. 31, 2021 | May 31, 2021 | Jan. 31, 2021 | Apr. 30, 2020 | Mar. 31, 2020 | Feb. 29, 2020 | Dec. 31, 2018 | Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
In-process research and development |  |  |  |  |  |  |  |  |  |  | $ 2,000,000 |
Accounts payable | $ 23,049,000 |  |  |  |  |  |  |  |  | $ 3,353,000 |  | $ 23,049,000
License Agreement | Novartis Pharma AG |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment | 20,000,000.0 |  |  |  |  |  |  |  |  |  |  |
In-process research and development |  |  |  |  |  |  |  |  |  |  |  | 100,000,000.0
Accounts payable | 20,000,000.0 |  |  |  |  |  |  |  |  | 0 |  | 20,000,000.0
Accrued milestone payment as underlying contingencies | 0 |  |  |  |  |  |  |  |  | 0 |  | 0
Stock issued, value | $ 80,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Stock issued and sold | 12,307,692 |  |  |  |  |  |  |  |  |  |  |
License Agreement | Novartis Pharma AG | Maximum |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Development and regulatory milestone payments obligation | $ 80,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Sales milestone payments obligation | 200,000,000.0 |  |  |  |  |  |  |  |  |  |  |
License Agreement | NiKang Therapeutics, Inc. |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment |  |  |  |  |  |  |  | $ 5,000,000.0 |  |  |  |
Reimbursement of certain initial manufacturing costs |  |  |  |  |  |  |  | 400,000 |  |  |  |
Payment for US patent application |  |  |  |  |  | $ 7,000,000.0 |  |  |  |  |  |
In-process research and development |  |  |  |  |  |  |  |  |  | 0 | 0 |
Accrued milestone payment as underlying contingencies | 0 |  |  |  |  |  |  |  |  | 0 |  | 0
License Agreement | NiKang Therapeutics, Inc. | First Licensed Product |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Payment of development and regulatory milestone obligation |  |  |  |  | $ 4,000,000.0 |  |  |  |  |  |  |
License Agreement | NiKang Therapeutics, Inc. | First Licensed Product | Maximum |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Development and regulatory milestone payments obligation |  |  |  |  |  |  |  | 16,000,000.0 |  |  |  |
Commercial milestone payments obligation |  |  |  |  |  |  |  | 157,000,000.0 |  |  |  |
License Agreement | NiKang Therapeutics, Inc. | Second Licensed Product |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Development and regulatory milestone payments obligation |  |  |  |  |  |  |  | 12,000,000.0 |  |  |  |
Commercial milestone payments obligation |  |  |  |  |  |  |  | $ 151,000,000.0 |  |  |  |
License Agreement | Katmai Pharmaceuticals, Inc. |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment |  |  |  |  |  |  | $ 5,700,000 |  |  |  |  |
Payment of development and regulatory milestone obligation |  | $ 2,000,000.0 |  |  |  |  |  |  |  |  |  |
In-process research and development |  |  |  |  |  |  |  |  |  | 0 | 2,000,000.0 |
Accrued milestone payment as underlying contingencies | 0 |  |  |  |  |  |  |  |  | 0 |  | 0
License Agreement | Katmai Pharmaceuticals, Inc. | Series B-1 Convertible Preferred Stock and Series B-2 Convertible Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock issued, value |  |  |  |  |  |  | $ 2,700,000 |  |  |  |  |
License Agreement | Katmai Pharmaceuticals, Inc. | Series B-1 Convertible Preferred Stock and Series B-2 Convertible Preferred Stock | IPO |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Conversion of convertible preferred stock into common stock |  |  |  |  |  |  | 395,555 |  |  |  |  |
License Agreement | Katmai Pharmaceuticals, Inc. | Series B-1 Convertible Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock issued, value |  |  |  |  |  | $ 1,800,000 |  |  |  |  |  |
Stock issued and sold |  |  |  |  |  | 356,000 |  |  |  |  |  |
License Agreement | Katmai Pharmaceuticals, Inc. | Series B-2 Convertible Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock issued, value |  |  |  |  | $ 900,000 |  |  |  |  |  |  |
Stock issued and sold |  |  |  |  | 118,666 |  |  |  |  |  |  |
License Agreement | Katmai Pharmaceuticals, Inc. | Maximum |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Development and regulatory milestone payments obligation |  |  |  |  |  |  | $ 26,000,000.0 |  |  |  |  |
Commercial milestone payments obligation |  |  |  |  |  |  | $ 101,000,000.0 |  |  |  |  |
License Agreement | LifeArc |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment |  |  |  |  |  | $ 0 |  |  |  |  |  |
In-process research and development |  |  |  |  |  |  |  |  |  | 0 | 0 |
Accrued milestone payment as underlying contingencies | 0 |  |  |  |  |  |  |  |  | 0 |  | 0
One-time license payment |  |  |  |  |  | 75,000 |  |  |  |  |  |
License Agreement | LifeArc | Maximum |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Development and regulatory milestone payments obligation |  |  |  |  |  | 11,000,000.0 |  |  |  |  |  |
Sales milestone payments obligation |  |  |  |  |  | $ 50,000,000.0 |  |  |  |  |  |
License Agreement | The Regents |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment |  |  |  |  |  |  |  |  | $ 50,000 |  |  |
In-process research and development |  |  |  |  |  |  |  |  |  | 0 | $ 0 |
Sales milestone payments obligation |  |  |  |  |  |  |  |  | $ 2,000,000.0 |  |  |
Percentage of third tier sublicensing fees |  |  |  |  |  |  |  |  | 30.00% |  |  |
Cash payments in license agreement upon achievement of corporate milestone |  |  | $ 1,700,000 |  |  |  |  |  |  |  |  |
Milestones accrued | $ 0 |  |  |  |  |  |  |  |  | $ 0 |  | $ 0
License Agreement | The Regents | Common Stock |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock issued and sold |  |  |  | 944,945 |  |  |  |  |  |  |  |
License Agreement | The Regents | Maximum |  |  |  |  |  |  |  |  |  |  |  |
License Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Development and regulatory milestone payments obligation |  |  |  |  |  |  |  |  | $ 6,400,000 |  |  |

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