XOMA Transaction - Additional information (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021	Dec. 31, 2019
Royalty Purchase Agreement [member]
Upfront payment received	$ 13.5
Milestone payment received in the future	$ 20.0
DOT-1 License Agreement [Member] | License Agreement Terms [Member]
Potential pre-commercialization payments receivable		$ 57.0
Development milestone payment received		$ 3.0
Regulatory, commercial milestones payments and double-digit royalty payments, receivable			$ 57.0