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Balance Sheet Components - Additional Information (Detail) - USD ($) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2021 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Jul. 31, 2021
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Other-than-temporary impairment loss | $ 0 |  |  |  |
Net unbilled co-development revenue | 8,000,000 | $ 8,000,000 | $ 0 |  |
Depreciation expense |  | 10,170,000 | 11,678,000 | $ 11,147,000 |
Profit share liability | 15,857,000 | 15,857,000 | 6,547,000 |  |
Acquired in-process research and development asset | 35,000,000 | 35,000,000 | $ 0 |  |
Eluminex [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Unbilled upfront payment | 8,000,000.0 | 8,000,000.0 |  |  | $ 8,000,000.0
AstraZeneca Agreements [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Net unbilled co-development revenue | 9,100,000 | 9,100,000 |  |  |
HiFiBiO Agreement [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Acquired in-process research and development asset | $ 35,000,000.0 | $ 35,000,000.0 |  |  |
U.S. [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Percentage of pre-launch inventory capitalized of aggregate inventory balance | 38.00% | 38.00% | 29.00% |  |
Europe [Member] | Astellas Agreement [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Transfer price true up | $ 49,800,000 | $ 49,800,000 |  |  |
China [Member] | AstraZeneca Agreements [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Profit share liability | $ 7,900,000 | $ 7,900,000 | $ 7,000,000.0 |  |

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