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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Collaboration and License Agreements - Additional Information (Detail) - USD ($)	1 Months Ended			12 Months Ended
	May 31, 2017	Jun. 30, 2015	Feb. 28, 2010	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2004
Licensing Agreement [Line Items]
Research and development (including amounts with related parties)				$ 64,483,000	$ 49,785,000	$ 55,718,000
Due to related parties				5,269,000	486,000
Milestone payments				0
Rush University Medical Center License Agreement
Licensing Agreement [Line Items]
Period of license agreement							12 years
Minimum annual royalty payment							$ 25,000
Payments in license agreement							2,500,000
Minimum sales milestone of license for first year							$ 300,000
Viracta Therapeutics, Inc.
Licensing Agreement [Line Items]
License agreement termination notice period	90 days
Viracta Therapeutics, Inc. \| Minimum
Licensing Agreement [Line Items]
Milestone Payment Amount	$ 10,000,000.0
Viracta Therapeutics, Inc. \| Maximum
Licensing Agreement [Line Items]
Milestone Payment Amount	$ 25,000,000.0
ImmunityBio
Licensing Agreement [Line Items]
Research and development (including amounts with related parties)				$ 300,000	100,000	100,000
Related party, agreement renewal term		1 year
Joint COVID 19 Collaboration Development Agreement
Licensing Agreement [Line Items]
Term of agreement				5 years
Additional term of agreement renewable upon mutual agreement				5 years
Joint COVID 19 Collaboration Development Agreement \| Sales
Licensing Agreement [Line Items]
Profit sharing percentage				60.00%
Joint COVID 19 Collaboration Development Agreement \| ImmunityBio
Licensing Agreement [Line Items]
Research and development (including amounts with related parties)				$ 8,400,000
Due to related parties				3,300,000
Joint COVID 19 Collaboration Development Agreement \| ImmunityBio \| Program Equipment Related Costs
Licensing Agreement [Line Items]
Research and development (including amounts with related parties)				5,000,000.0
Joint COVID 19 Collaboration Development Agreement \| ImmunityBio \| Net Program Related Costs
Licensing Agreement [Line Items]
Research and development (including amounts with related parties)				$ 3,400,000
Joint COVID 19 Collaboration Development Agreement \| ImmunityBio \| Sales
Licensing Agreement [Line Items]
Profit sharing percentage				40.00%
Clinical Trial Cost Allocation Agreement \| ImmunityBio
Licensing Agreement [Line Items]
Research and development (including amounts with related parties)				$ 1,100,000	35,700
Due to related parties				300,000	0
Related party, agreement renewal term		1 year
Precigen License Agreement
Licensing Agreement [Line Items]
Milestone Payment Amount				0	0	0
License agreement term (years)			17 years
Agreement one time fee			$ 400,000
Milestone payments				$ 0	$ 0	$ 0
Precigen License Agreement \| First IND Filing
Licensing Agreement [Line Items]
Milestone Payment Amount			100,000
Precigen License Agreement \| First Phase II Clinical Trial
Licensing Agreement [Line Items]
Milestone Payment Amount			100,000
Precigen License Agreement \| First Phase III Clinical Trial
Licensing Agreement [Line Items]
Milestone Payment Amount			400,000
Precigen License Agreement \| Commercial Sale Related to Licensed Products
Licensing Agreement [Line Items]
Milestone Payment Amount			$ 500,000