Commitments and Contingencies - Summary of Unconditional Purchase Obligations (Detail) $ in Thousands	Dec. 31, 2020 USD ($)
Recorded Unconditional Purchase Obligation [Line Items]
Purchase obligations due 2021	$ 42,012
Purchase obligations due 2022	44,014
Total purchase obligations	86,026
Manufacture and Supply of Roxadustat [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Purchase obligations due 2021	14,114
Purchase obligations due 2022	10,951
Total purchase obligations	25,065
Manufacture and Supply of Pamrevlumab [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Purchase obligations due 2021	24,480
Purchase obligations due 2022	33,063
Total purchase obligations	57,543
Other Purchases [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Purchase obligations due 2021	3,418
Purchase obligations due 2022	0
Total purchase obligations	$ 3,418

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 http://asc.fasb.org/extlink&oid=121559207&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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- Definition

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.

+ References

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