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Collaboration and Licensing Agreements - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands					1 Months Ended			12 Months Ended
	Oct. 15, 2022	Oct. 15, 2021	Oct. 15, 2020	May 17, 2018	Oct. 31, 2021	Oct. 31, 2020	May 31, 2018	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Collaboration and Licensing Agreements:
Proceeds from the sale of common stock								$ 1,117
Revenue from contract with customer								20,968	$ 41,867	$ 23,028
License and milestone fees
Collaboration and Licensing Agreements:
Revenue from contract with customer								$ 910	15,000	21,223
Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1
Collaboration and Licensing Agreements:
Percentage of net profit sharing						60.00%
Number of days to terminate agreement								60 days
Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2
Collaboration and Licensing Agreements:
Percentage of net profit sharing							50.00%
License Agreement with Maruishi Pharmaceutical Co. Ltd
Collaboration and Licensing Agreements:
Earned milestone payment								$ 1,449
CSL Vifor Maximum \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1
Collaboration and Licensing Agreements:
Potential sales-based milestone payments			$ 240,000
Affiliated Entity \| Vifor International Ltd. \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1
Collaboration and Licensing Agreements:
Proceeds from the sale of common stock		$ 50,000
Common stock, shares issued					3,282,391
Purchase common stock per share amount					$ 15.23
Percentage of premium on common stock investment	20.00%
Stock issuance price measurement period	30 days
Premium from sale of stock										5,031
Affiliated Entity \| CSL Vifor \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1
Collaboration and Licensing Agreements:
Percentage of net profit sharing						40.00%
Affiliated Entity \| Vifor Fresenius Medical Care Renal Pharma Ltd. \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2
Collaboration and Licensing Agreements:
Number of days to terminate agreement				60 days
Termination notice effective period				12 months
Affiliated Entity \| Vifor Fresenius Medical Care Renal Pharma Ltd. \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 \| License and milestone fees
Collaboration and Licensing Agreements:
Revenue from contract with customer									$ 15,000	$ 15,000
Affiliated Entity \| Vifor Fresenius Medical Care Renal Pharma Ltd. \| Maximum \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2
Collaboration and Licensing Agreements:
Potential milestone payments				$ 440,000
Affiliated Entity \| Maruishi Pharmaceutical Co., Ltd. [Member] \| License Agreement with Maruishi Pharmaceutical Co. Ltd \| License and milestone fees
Collaboration and Licensing Agreements:
Revenue from contract with customer								$ 1,449