Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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The cash outflow associated with extending a long-term loan to a related party. Alternate caption: Payments for Advances to Affiliates.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

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Additional Loans Committed.

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Represents the amount of cash resources in hand for future use.

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Related party transaction expenses from transactions with related party advisory fees.

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Research and development service agreement aggregate payment.

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Temporary equity fair value disclosure.

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Related Party Transactions - Additional Information (Detail) - USD ($)			12 Months Ended
	Oct. 05, 2018	Jun. 29, 2016	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2015
Related Party Transaction [Line Items]
Change in fair value of derivative liability			$ 0	$ 0	$ 158,000
Amounts expensed for services incurred			80,361,000	57,858,000	54,052,000
Research and development expense			52,696,000	38,331,000	34,134,000
Expenses From Transactions With Related Party					2,000,000.0
MD Anderson License and the Research and Development Agreement Member [Member]
Related Party Transaction [Line Items]
Cash resources on hand			8,100,000
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
Expenses From Transactions With Related Party	$ 5,400,000
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	41,900,000	41,900,000
Intrexon Corporation/Precigen
Related Party Transaction [Line Items]
Amounts expensed for services incurred			$ 100,000	3,000,000.0	$ 8,100,000
Amount due to related party, current				$ 100,000
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
Vineti Inc \| Collaborative Arrangement
Related Party Transaction [Line Items]
Expenses From Transactions With Related Party			$ 29,000
Eden BioCell [Member]
Related Party Transaction [Line Items]
Payments to Fund Long-term Loans to Related Parties			10,000,000.0
Additional Loans Committed			$ 25,000,000.0