Commitments and Contingencies - Summary of Outstanding Non-cancelable Purchase Obligations (Detail) $ in Thousands	Dec. 31, 2024 USD ($)
Recorded Unconditional Purchase Obligation [Line Items]
Purchase obligations due 2025	$ 2,134
Purchase obligations due 2026	636
Total	2,770
General Purchases and Other Programs [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Purchase obligations due 2025	1,796
Purchase obligations due 2026	0
Total	1,796
Manufacture and Supply of FG - 3246 [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Purchase obligations due 2025	223
Purchase obligations due 2026	0
Total	223
Manufacture and Supply of Roxadustat [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Purchase obligations due 2025	115
Purchase obligations due 2026	636
Total	$ 751

Amount of the recorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482648/440-10-50-6

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Amount of recorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of recorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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