Financial Commitments and Contingencies and Key License Agreements - Additional Information (Details)				1 Months Ended
	Jan. 01, 2022 USD ($)	Aug. 31, 2021 plaintiff	May 28, 2021 patent	Dec. 31, 2020 USD ($)	Apr. 30, 2019 product	Apr. 30, 2018 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Mar. 31, 2021 USD ($)
Long-term Purchase Commitment [Line Items]
Facility and equipment under lease							$ 2,107,000	$ 2,505,000
Licensors | product					2
Accrued payroll and benefits							6,633,000	11,971,000
Deferred compensation liability, current and noncurrent							10,500,000	11,200,000
Bioverativ Therapeutics Inc., Subject Patents
Long-term Purchase Commitment [Line Items]
Patents allegedly infringed | patent			3
Hanmi Pharmaceutical Co. Ltd. (“Hanmi”) | Eflapegrastim, Co-Development and Commercialization Agreement
Long-term Purchase Commitment [Line Items]
Reduction in accrued liabilities	$ 11,200,000
Potential payments based on additional achievements of regulatory milestones	10,000,000
Hanmi Pharmaceutical Co. Ltd. (“Hanmi”) | Poziotinib: In-License Agreement
Long-term Purchase Commitment [Line Items]
Achievement of regulatory milestones potential payments	18,000,000
Supplemental royalty milestone limit	$ 15,000,000
Therapyx
Long-term Purchase Commitment [Line Items]
Asset purchase agreement, upfront payment				$ 800,000
Entity plaintiff | Shareholder Litigation
Long-term Purchase Commitment [Line Items]
Number of plaintiffs | plaintiff		1
Plaintiffs, Individual | Shareholder Litigation
Long-term Purchase Commitment [Line Items]
Number of plaintiffs | plaintiff		4
MD Anderson
Long-term Purchase Commitment [Line Items]
Payment of upfront fee						$ 500,000
Chief Executive Officer
Long-term Purchase Commitment [Line Items]
Accrued payroll and benefits							2,600,000		$ 3,100,000
Plan | Therapyx
Long-term Purchase Commitment [Line Items]
Potential payments based on additional achievements of regulatory milestones				2,200,000
Potential payments based on worldwide annual net sales				167,500,000
Plan | Therapyx | I L12 Product
Long-term Purchase Commitment [Line Items]
Potential payments based on additional achievements of regulatory milestones				30,000,000
Plan | Therapyx | Each new indication approved
Long-term Purchase Commitment [Line Items]
Potential payments based on additional achievements of regulatory milestones				$ 2,500,000
Plan | MD Anderson
Long-term Purchase Commitment [Line Items]
Achievement of regulatory milestones potential payments						6,000,000
Potential payments based on achievement of sales milestones						$ 24,000,000
Office and research facilities
Long-term Purchase Commitment [Line Items]
Facility and equipment under lease							1,700,000	2,100,000
Office equipment
Long-term Purchase Commitment [Line Items]
Facility and equipment under lease							$ 400,000	$ 400,000
Minimum
Long-term Purchase Commitment [Line Items]
Remaining lease term (in years)							1 year
Maximum
Long-term Purchase Commitment [Line Items]
Remaining lease term (in years)							4 years