Commitments and Contingencies - Summary of Outstanding Non-cancelable Purchase Obligations (Detail) $ in Thousands	Dec. 31, 2022 USD ($)
Recorded Unconditional Purchase Obligation [Line Items]
Purchase obligations due 2023	$ 27,909
Purchase obligations due 2024	25,846
Total	53,755
Manufacture and Supply of Pamrevlumab [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Purchase obligations due 2023	85
Purchase obligations due 2024	22,310
Total	22,395
Manufacture and Supply of Roxadustat [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Purchase obligations due 2023	6,126
Purchase obligations due 2024	2,369
Total	8,495
Other Purchases and Programs [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Purchase obligations due 2023	21,698
Purchase obligations due 2024	1,167
Total	$ 22,865

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 6
-URI https://asc.fasb.org/extlink&oid=123406679&loc=d3e25383-109308

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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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