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Summary of Significant Accounting Policies - Additional Information (Detail) |  | 12 Months Ended
--- | --- | ---
Jun. 16, 2021 USD ($) | Dec. 31, 2022 USD ($) Segment | 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 |  | $ 2,100,000 | $ 2,100,000
Cash and cash equivalents |  | $ 155,700,000 | 171,223,000
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
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 |  | $ (1,557,688,000) | (1,264,034,000)
Accumulated other comprehensive loss |  | $ (5,720,000) | (4,163,000)
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 additional future clinical, regulatory, and commercial milestone payments | $ 345,000,000 |  |
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 |  | $ 92,500,000 | $ 91,200,000
Accounts Receivable from Distributors [Member] | Credit Concentration Risk [Member] | Roxadustat [Member] |  |  |
Accounting Policy [Line Items] |  |  |
Concentration risk, percentage |  | 10.00% |

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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(30)(a)(4)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI https://asc.fasb.org/extlink&oid=126968391&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(23)(a)(3)) -URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI https://asc.fasb.org/extlink&oid=126968391&loc=SL7669686-108580 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (h)(2) -URI https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (g)(2)(ii) -URI https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI https://asc.fasb.org/extlink&oid=126968391&loc=d3e681-108580 + Details
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