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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	Apr. 30, 2022	Oct. 31, 2021	Oct. 31, 2020	May 31, 2018	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenues									$ 41,867	$ 23,028	$ 135,082
License and Milestone Fees
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenues									15,000	21,223	134,439
Collaborative Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenues									16,572	706
Commercial Supply Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenues									$ 10,223	701
Clinical Compound Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenues										398	$ 643
Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing							60.00%				60.00%
Number of days to terminate agreement									60 days
Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing								50.00%
CSL Vifor Maximum [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential sales-based milestone payments			$ 240,000
Vifor Fresenius Medical Care Renal Pharma Ltd. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Non-refundable, non-creditable upfront payment				$ 50,000
Vifor Fresenius Medical Care Renal Pharma Ltd. [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of days to terminate agreement				60 days
Termination notice effective period				12 months
Vifor Fresenius Medical Care Renal Pharma Ltd. [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 [Member] \| License and Milestone Fees
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenues					$ 15,000					15,000
Maruishi Pharmaceutical Co., Ltd. [Member] \| License and Milestone Fees
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenues										1,192
Maruishi Pharmaceutical Co., Ltd. [Member] \| Clinical Compound Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenues										37	$ 528
Vifor International Ltd. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Closing prices of company common stock description				over a pre-determined average closing price of the Company’s common stock.
Vifor International Ltd. [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing							40.00%				40.00%
Common stock, shares issued						3,282,391	2,939,552
Proceeds from the sale of common stock		$ 50,000	$ 50,000
Purchase common stock per share amount						$ 15.23	$ 17.0094
Premium from sale of stock										5,031
Percentage of premium on common stock investment	20.00%
Stock issuance price measurement period	30 days
Vifor International Ltd. [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member] \| License [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Non-refundable, non-creditable upfront payment							$ 100,000
Vifor International Ltd. [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member] \| License and Milestone Fees
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Premium from sale of stock						$ 11,551
Vifor International Ltd. [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Common stock, shares issued				1,174,827
Purchase of common stock value				$ 20,000
Purchase common stock per share amount				$ 17.024
Premium from sale of stock				$ 5,444
CSL Vifor [Member] \| License and Milestone Fees
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenues									$ 15,000	20,031	$ 133,813
CSL Vifor [Member] \| Collaborative Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenues									16,572	0	0
CSL Vifor [Member] \| Commercial Supply Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenues									$ 10,223	701
CSL Vifor [Member] \| Clinical Compound Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenues										$ 361	$ 115
CSL Vifor [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing							40.00%
Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 [Member] \| Maximum [Member] \| Regulatory and Commercial Milestones [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential milestone payments				$ 440,000