Description of Business - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		9 Months Ended	10 Months Ended
	Mar. 09, 2021	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
NantKwest
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Ownership percentage held by stockholders upon consummation of merger	28.50%
Executive Chairman and Global Chief Scientific and Medical Officer
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Ownership percentage held by Executive Chairman and Global Chief Scientific and Medical Officer upon consummation of merger	81.80%
Selling General and Administrative Expenses
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Merger-related costs		$ 13.0	$ 23.3
NantCell
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Common stock, par value (in dollars per share)	$ 0.001
Merger exchange ratio	0.8190
Ownership percentage held by stockholders upon consummation of merger	71.50%