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Balance Sheet Components - Additional Information (Detail) - USD ($) | 12 Months Ended | 36 Months Ended |
--- | --- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2022 | Jul. 31, 2021
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Other-than-temporary impairment loss |  |  |  | $ 0 |
Net unbilled co-development revenue | $ 0 | $ 8,000,000 |  | 0 |
Depreciation expense | 10,017,000 | 10,170,000 | $ 11,678,000 |  |
API and bulk drug product price true-up | 75,055,000 | 0 |  | 75,055,000 |
Acquired in-process research and development asset | 0 | 35,000,000 |  | 0 |
Cash and cash equivalents | 155,700,000 | 171,223,000 |  | 155,700,000 |
Eluminex Agreements [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Unbilled upfront payment |  | 8,000,000.0 |  |  | $ 8,000,000.0
Astellas Japan Agreement [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
API and bulk drug product price true-up | 6,500,000 |  |  | 6,500,000 |
Astellas Europe Agreement [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
API and bulk drug product price true-up | 57,400,000 |  |  | 57,400,000 |
AstraZeneca Agreements [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Net unbilled co-development revenue | 17,500,000 | 9,100,000 |  | 17,500,000 |
API and bulk drug product price true-up | 11,200,000 |  |  | 11,200,000 |
HiFiBiO Agreement [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Acquired in-process research and development asset |  | 35,000,000.0 |  |  |
Europe [Member] | Astellas Agreement [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Transfer price true up |  | 49,800,000 |  |  |
Foreign subsidiaries [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Cash and cash equivalents | $ 92,500,000 | $ 91,200,000 |  | $ 92,500,000 |

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