Investments - Additional Information (Details) - USD ($)			1 Months Ended		12 Months Ended
	Dec. 07, 2021	Mar. 09, 2021	Jul. 31, 2021	May 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Equity Method Investments [Line Items]
Equity method investment, impairment losses					$ 0	$ 3,800,000
Common stock, shares outstanding (in shares)					314,573,225	275,285,582
Proceeds from sale of marketable investments					$ 124,767,000	$ 0	$ 0
NantKwest, Inc. and ImmunityBio
Schedule Of Equity Method Investments [Line Items]
Percentage of business acquisition		100.00%
Receive shares of common stock for each outstanding share		$ 0.8190
ImmunityBio
Schedule Of Equity Method Investments [Line Items]
Common stock, shares outstanding (in shares)		10,000,000
Realized gain (loss) on marketable investments					$ 24,100,000
Marketable investments shares sold					8,190,000
Proceeds from sale of marketable investments					$ 124,000,000.0
ImmunityBio | Common Stock
Schedule Of Equity Method Investments [Line Items]
Remaining shares					0
ImmunityBio | Maximum
Schedule Of Equity Method Investments [Line Items]
Common stock received		8,190,000
Aardvark | Series B Preferred Stock
Schedule Of Equity Method Investments [Line Items]
Payments to acquire equity investment			$ 5,000,000.0	$ 5,000,000.0	$ 10,000,000.0
Shares purchased under equity investment			3,888,932	3,888,932	7,777,864
Deverra
Schedule Of Equity Method Investments [Line Items]
Payments to acquire equity investment					$ 4,100,000
Aggregate principal amount					6,000,000.0
Unpaid accrued interest					100,000
Deverra | Common Stock
Schedule Of Equity Method Investments [Line Items]
Payments to acquire equity investment					$ 10,200,000
Shares purchased under equity investment					5,622,703
Deverra | Promissory Note
Schedule Of Equity Method Investments [Line Items]
Payments to acquire equity investment	$ 1,000,000.0
Elsie | Series A Preferred Stock
Schedule Of Equity Method Investments [Line Items]
Payments to acquire equity investment					$ 10,000,000.0
Shares purchased under equity investment					10,000,000