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Commitments and Contingencies - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)
Commitments And Contingencies [Line Items]
Outstanding non-cancelable contract obligations	$ 23.5
Manufacture and Supply of Roxadustat [Member]
Commitments And Contingencies [Line Items]
Outstanding non-cancelable contract obligations	11.9
Research and Pre-Clinical Stage Development Programs [Member]
Commitments And Contingencies [Line Items]
Future milestone payments	11.0
Other Purchases [Member]
Commitments And Contingencies [Line Items]
Outstanding non-cancelable contract obligations	$ 0.6

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- Definition

Commitments and contingencies.

+ References

No definition available.

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- Definition

Future milestone payments.

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No definition available.

+ Details

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X

- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

No definition available.

+ Details

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- Details

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- Details

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