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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Related Party Transactions - Additional Information (Detail) - USD ($)		12 Months Ended
	Jun. 29, 2016	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2015
Related Party Transaction [Line Items]
Change in fair value of derivative liability		$ 0	$ 158,000	$ (1,295,000)
Amounts expensed for services incurred		57,858,000	54,052,000	59,882,000
Research and development expense		38,331,000	34,134,000	45,084,000
MD Anderson License and the Research and Development Agreement Member [Member]
Related Party Transaction [Line Items]
Cash resources on hand		20,300,000
Series 1 Preferred Stock
Related Party Transaction [Line Items]
Temporary equity, fair value		18,900,000
Change in fair value of derivative liability		1,300
License Agreement \| M.D. Anderson Cancer Center
Related Party Transaction [Line Items]
Issuance of common stock in licensing agreement (in shares)					11,722,163
Research and development expense					$ 67,300,000
Cooperative Research and Development Agreement \| M.D. Anderson Cancer Center
Related Party Transaction [Line Items]
Research and development service agreement aggregate payments		41,900,000
Intrexon Corporation/Precigen
Related Party Transaction [Line Items]
Amounts expensed for services incurred		3,000,000	8,100,000	$ 21,400,000
Amount due to related party, current		100,000	$ 1,900,000
Research and development expense		$ 1,000,000
Intrexon Corporation/Precigen \| Series 1 Preferred Stock
Related Party Transaction [Line Items]
Issuance of common stock in licensing agreement (in shares)	100,000	11,415