Revenue Recognition - Disaggregation of Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Disaggregation of Revenue [Line Items]
Total revenue	$ 2,135	$ 6,165
Other revenue (non-cash)
Disaggregation of Revenue [Line Items]
Total revenue	623	0
Other revenue (non-cash) | Maruishi Agreement [Member]
Disaggregation of Revenue [Line Items]
Total revenue	333
Other revenue (non-cash) | Affiliated Entity [Member] | CSL Vifor | CSL Vifor Kapruvia [Member]
Disaggregation of Revenue [Line Items]
Total revenue	290
Collaborative revenue
Disaggregation of Revenue [Line Items]
Total revenue	788	2,750
Collaborative revenue | Affiliated Entity [Member] | CSL Vifor | CSL Vifor Profit Sharing
Disaggregation of Revenue [Line Items]
Total revenue	788	2,750
Commercial supply revenue
Disaggregation of Revenue [Line Items]
Total revenue	640	3,191
Commercial supply revenue | Affiliated Entity [Member] | CSL Vifor | CSL Vifor Korsuva [Member]
Disaggregation of Revenue [Line Items]
Total revenue	640	3,191
Clinical compound revenue
Disaggregation of Revenue [Line Items]
Total revenue	84	99
Clinical compound revenue | Maruishi Agreement [Member]
Disaggregation of Revenue [Line Items]
Total revenue	84	99
Royalty revenue
Disaggregation of Revenue [Line Items]
Total revenue		125
Royalty revenue | Affiliated Entity [Member] | CSL Vifor | CSL Vifor Kapruvia [Member]
Disaggregation of Revenue [Line Items]
Total revenue	$ 0	$ 125