License, Collaboration and Other Significant Agreements - Deferred Revenue (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Deferred Revenue:
Short-Term	$ 10,440	$ 20,906
Long-Term	65,356	$ 21,474
Total	75,796
Mitsubishi Tanabe Pharma Corporation | MTPC Agreement
Deferred Revenue:
Short-Term	0
Long-Term	0
Total	0
Otsuka Pharmaceutical Company. Ltd. | Otsuka U.S. Agreement
Deferred Revenue:
Short-Term	6,192
Long-Term	16,087
Total	22,279
Otsuka Pharmaceutical Company. Ltd. | Otsuka International Agreement
Deferred Revenue:
Short-Term	4,248
Long-Term	5,973
Total	10,221
Vifor Pharma
Deferred Revenue:
Short-Term	0
Long-Term	43,296
Total	$ 43,296