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Related Party Agreements - Additional Information (Detail)		1 Months Ended							3 Months Ended
	Dec. 01, 2017 USD ($) ft²	Mar. 31, 2018 USD ($) Officer	Apr. 30, 2017 USD ($) ft²	Sep. 30, 2016 USD ($) ft²	Apr. 30, 2016 USD ($)	Mar. 31, 2016	Nov. 30, 2015 USD ($) ft²	Jun. 30, 2015	Mar. 31, 2018 USD ($) Officer Patient	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Feb. 28, 2017 USD ($)
Related Party Transaction [Line Items]
Research and development									$ 13,991,000	$ 9,248,000
Due to related parties		$ 2,456,000							2,456,000		$ 2,363,000
Prepaid expenses and other current assets		$ 4,958,000							4,958,000		$ 4,152,000
Selling, general and administrative expense									14,298,000	16,227,000
Liquid Genomics, Inc.
Related Party Transaction [Line Items]
Initial term of agreement entered into with the related party by the entity		5 years
Related party, agreement renewal term		1 year
Related party agreement payments due period from invoice date		30 days
Research and development									37,000
Due to related parties		$ 37,000							37,000
Chan Soon-Shiong Institutes for Medicine (CSSIM) \| California
Related Party Transaction [Line Items]
Research and development									700,000
Due to related parties		$ 700,000							$ 700,000
Number of officers \| Officer		2							2
Tensorcom, Inc \| San Diego California
Related Party Transaction [Line Items]
Period of agreement									Lease from May 1, 2017 through April 30, 2018
Number of square foot of facility leased \| ft²			6,557
Base rent - monthly			$ 25,000
Percentage of annual increase of base rent			3.00%
Due between parties		$ 0							$ 0
Tensorcom, Inc \| San Diego California \| Other Income
Related Party Transaction [Line Items]
Sublease revenue recognized									100,000
VivaBioCell S.p.A.
Related Party Transaction [Line Items]
Research and development									$ 100,000	100,000
Prepaid expenses and other current assets												$ 600,000
Doug St, LLC
Related Party Transaction [Line Items]
Period of agreement									The lease runs from July 2016 through July 2023. The Company has the option to extend the lease for an additional three year term through July 2026. The monthly rent is $0.1 million with annual increases of 3% beginning in July 2017.
Base rent - monthly				$ 100,000
Percentage of annual increase of base rent				3.00%
Due between parties		0							$ 0
Annual percentage increases to base rent commencement date				Jul. 31, 2017
Doug St, LLC \| Research and Development
Related Party Transaction [Line Items]
Rent expense									$ 100,000	100,000
Doug St, LLC \| El Segundo California
Related Party Transaction [Line Items]
Number of square foot of facility leased \| ft²				24,250
Altor
Related Party Transaction [Line Items]
Maximum number of patients in phase 1 and 2 for clinical trials \| Patient									400
Supplies and milestone charges for conducting clinical trials									$ 0	0
NantBioScience
Related Party Transaction [Line Items]
Initial term of agreement entered into with the related party by the entity						5 years
Research and development									$ 100,000	$ 100,000
Number of square foot of facility leased \| ft²	1,965
Base rent - monthly	$ 10,000
Percentage of annual increase of base rent	3.00%
Sublease term	24 months
Sublease termination notice period	30 days
Prepayment of funding amount			$ 600,000		$ 600,000
Research and development expense, ratable payment period									12 months	12 months
NantBioScience \| Prepaid Expenses and Current Assets
Related Party Transaction [Line Items]
Due between parties										$ 10,000
NantBioScience \| Other Income
Related Party Transaction [Line Items]
Sublease revenue recognized										31,000
NantWorks
Related Party Transaction [Line Items]
Due to related parties		1,600,000							$ 1,600,000
Number of square foot of facility leased \| ft²							9,500
Base rent - monthly							$ 47,000
Percentage of annual increase of base rent							3.00%
Annual percentage increases to base rent commencement date							Jan. 31, 2017
NantWorks \| Shared Services Agreement
Related Party Transaction [Line Items]
Research and development									900,000	800,000
Selling, general and administrative expense									800,000	1,200,000
NantWorks \| Reimbursements \| Shared Services Agreement
Related Party Transaction [Line Items]
Research and development									600,000	100,000
Selling, general and administrative expense									100,000	100,000
NantWorks \| Research and Development
Related Party Transaction [Line Items]
Rent expense									47,000	47,000
NantOmics
Related Party Transaction [Line Items]
Initial term of agreement entered into with the related party by the entity								5 years
Related party, agreement renewal term								1 year
Research and development									42,000	0
Due to related parties		100,000							100,000
NantCell Inc
Related Party Transaction [Line Items]
Initial term of agreement entered into with the related party by the entity								5 years
Related party, agreement renewal term								1 year
Research and development									0	$ 300,000
Due to related parties		0							0
Prepaid expenses and other current assets		$ 200,000							$ 200,000