Revenue Recognition - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Collaboration Arrangement [Line Items]
Accounts receivable, net - related party	$ 1,718		$ 2,765
Total revenue	2,135	$ 6,165
Other receivables	506		555
Commercial supply revenue
Collaboration Arrangement [Line Items]
Total revenue	640	3,191
Royalty revenue
Collaboration Arrangement [Line Items]
Total revenue		125
Collaborative revenue
Collaboration Arrangement [Line Items]
Total revenue	788	2,750
Clinical compound revenue
Collaboration Arrangement [Line Items]
Total revenue	84	99
Other revenue (non-cash)
Collaboration Arrangement [Line Items]
Total revenue	623	0
CSL Vifor, Maruishi and CKDP Agreements [Member]
Collaboration Arrangement [Line Items]
Other contract Assets	0		0
Other contract liabilities	0		0
Maruishi Agreement [Member]
Collaboration Arrangement [Line Items]
Other receivables	346		415
Maruishi Agreement [Member] | Clinical compound revenue
Collaboration Arrangement [Line Items]
Total revenue	84	99
Maruishi Agreement [Member] | Other revenue (non-cash)
Collaboration Arrangement [Line Items]
Total revenue	333
Affiliated Entity [Member] | CSL Vifor
Collaboration Arrangement [Line Items]
Accounts receivable, net - related party	1,718		$ 2,765
Affiliated Entity [Member] | CSL Vifor | CSL Vifor Profit Sharing | Collaborative revenue
Collaboration Arrangement [Line Items]
Total revenue	788	2,750
Affiliated Entity [Member] | CSL Vifor | CSL Vifor Korsuva [Member] | Commercial supply revenue
Collaboration Arrangement [Line Items]
Total revenue	640	3,191
Affiliated Entity [Member] | CSL Vifor | CSL Vifor Korsuva [Member] | Commercial Supply Revenue With Associated Costs Of Goods Sold [Member]
Collaboration Arrangement [Line Items]
Cost of goods sold	620	2,590
Affiliated Entity [Member] | CSL Vifor | CSL Vifor Kapruvia [Member] | Royalty revenue
Collaboration Arrangement [Line Items]
Total revenue	0	$ 125
Affiliated Entity [Member] | CSL Vifor | CSL Vifor Kapruvia [Member] | Other revenue (non-cash)
Collaboration Arrangement [Line Items]
Total revenue	$ 290