Revenue and Deferred Revenue (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended		6 Months Ended
	Feb. 09, 2021	Nov. 30, 2020	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Contract revenue			$ 653	$ 540	$ 2,301	$ 911
Deferred revenue, current			0		$ 0		$ 2,301
License
Disaggregation of Revenue [Line Items]
Contract termination period, curable breach					60 days
Contract termination period, incurable breach					90 days
Vifor Pharma | License
Disaggregation of Revenue [Line Items]
Upfront and near-term milestone payment, entitled to receive		$ 60,000
Contract with customer, liability		30,000
Equity securities	$ 30,000
Post-approval milestone payment, entitled to receive		260,000
Sales-related milestone payment, entitled to receive		1,585,000
Total milestone payment, entitled to receive		$ 1,905,000
Royalty rates (up to)		40.00%
Contract with customer, revenue recognized		$ 15,000	15,000
Transaction price, percent of upfront payment		50.00%
Contract revenue			700	$ 500	$ 2,300	$ 900
Deferred revenue, current			$ 0		$ 0		$ 2,300
Vifor Pharma | License | IPO
Disaggregation of Revenue [Line Items]
Equity investment received	5,000
Vifor Pharma | License | Private placement
Disaggregation of Revenue [Line Items]
Equity investment received	$ 25,000