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Summary of Significant Accounting Policies - Additional Information (Detail) |  | 12 Months Ended
--- | --- | ---
Jun. 16, 2021 USD ($) | Dec. 31, 2023 USD ($) Segment | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Accounting Policy [Line Items] |  |  |  |
Number of operating segment | Segment |  | 1 |  |
Highly liquid investment maturity period |  | three months or less |  |
Restricted time deposits |  | $ 1,700,000 | $ 2,100,000 |
Cash and cash equivalents |  | $ 113,688,000 | 155,700,000 |
Short term investments maturity |  | 12 months |  |
Long term Investments Maturity |  | 12 months |  |
Impairment of long-lived assets |  | $ 0 | 0 |
Impairment of inatangible assets finite lived |  | $ 0 | 0 | $ 0
Description of payment term |  | The period between the transfer of control of the promised goods and when the Company receives payment is based on 60-day payment terms. |  |
Description of sales return |  | distributors can request to return product to the Company only due to quality issues or for product purchased within one year prior to the product’s expiration date. |  |
Accumulated deficit |  | $ (1,841,920,000) | (1,557,688,000) |
Accumulated other comprehensive loss |  | $ (6,875,000) | (5,720,000) |
AstraZeneca Agreements [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Profit share percent |  | 50.00% |  |
HiFiBiO Agreement [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Initial upfront payment | $ 25,000,000.0 |  |  |
Maximum R&D and regulatory milestone payments receivable |  | $ 175,000,000 |  |
Maximum sales milestones receivable |  | $ 170,000,000 |  |
Percentage of tiered royalties receivable |  | 10.00% |  |
HiFiBiO Agreement [Member] | IPR&D Asset [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Initial upfront payment |  |  |  | 60,000,000.0
HiFiBiO Agreement [Member] | Accrued Liabilities |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Initial upfront payment |  |  |  | $ 35,000,000.0
Minimum [Member] | Computer Equipment [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Property and equipment estimated useful life |  | 3 years |  |
Minimum [Member] | Laboratory Equipment [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Property and equipment estimated useful life |  | 3 years |  |
Minimum [Member] | Machinery [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Property and equipment estimated useful life |  | 3 years |  |
Minimum [Member] | Furniture and Fixtures [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Property and equipment estimated useful life |  | 3 years |  |
Maximum [Member] | Computer Equipment [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Property and equipment estimated useful life |  | 5 years |  |
Maximum [Member] | Laboratory Equipment [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Property and equipment estimated useful life |  | 5 years |  |
Maximum [Member] | Machinery [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Property and equipment estimated useful life |  | 5 years |  |
Maximum [Member] | Furniture and Fixtures [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Property and equipment estimated useful life |  | 5 years |  |
Foreign subsidiaries [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Cash and cash equivalents |  | $ 32,200,000 | $ 92,500,000 |
Accounts Receivable from Distributors [Member] | Credit Concentration Risk [Member] | Roxadustat [Member] |  |  |  |
Accounting Policy [Line Items] |  |  |  |
Concentration risk, percentage |  | 17.00% | 10.00% |

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