Commitment and Contingencies - Additional Information (Detail)	1 Months Ended		3 Months Ended		9 Months Ended
	Apr. 30, 2017 USD ($) ft²	Sep. 30, 2015 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($) ft²	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($) ft²	Dec. 31, 2016 USD ($)	Nov. 30, 2015 ft²	May 31, 2015 ft²
Commitments And Contingencies [Line Items]
Rent expense			$ 600,000	$ 800,000	$ 2,000,000	$ 2,200,000
Non cash build to suit lease asset			5,100,000		5,100,000
Property, plant and equipment, gross			77,749,000		77,749,000		$ 20,084,000
Doug St, LLC
Commitments And Contingencies [Line Items]
Base rent - monthly					$ 100,000
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.
Optional extended lease term					3 years
Percentage of annual increase of base rent					3.00%
Annual percentage increases to base rent commencement date					Jul. 31, 2017
Costs incurred			29,100,000		$ 29,100,000
Non cash build to suit lease asset			5,100,000		$ 5,100,000
Property and equipment estimated useful lives					39 years
Doug St, LLC | Research and Development
Commitments And Contingencies [Line Items]
Rent expense			100,000	100,000	$ 200,000	100,000
NantWorks
Commitments And Contingencies [Line Items]
Base rent - monthly					$ 47,000
Number of square foot of facility leased | ft²								9,500	9,500
Period of agreement					The license was effective in May 2015 and extends through December 2020. The Company has the option to extend the license through December 2023. The monthly license fee is $47,000 with annual increases of 3% beginning in January 2017.
Percentage of annual increase of base rent					3.00%
Annual percentage increases to base rent commencement date					Jan. 31, 2017
Costs incurred				3,500,000		3,500,000
Property and equipment estimated useful lives					39 years
NantWorks | Building Under Financing Lease
Commitments And Contingencies [Line Items]
Property, plant and equipment, gross			4,300,000		$ 4,300,000
NantWorks | Research and Development
Commitments And Contingencies [Line Items]
Rent expense			$ 47,000	$ 100,000	100,000	$ 300,000
El Segundo California | Doug St, LLC
Commitments And Contingencies [Line Items]
Number of square foot of facility leased | ft²				24,250		24,250
El Segundo California | Agreement to Purchase Commercial Building
Commitments And Contingencies [Line Items]
Area of Land | ft²	36,000
Escrow deposit	$ 5,000,000
Remaining purchase price paid including closing costs					$ 15,300,000
Base rent - monthly	$ 0
Escrow closed period					2017-09
USPTO
Commitments And Contingencies [Line Items]
Attorney's fees and expert witness fees		$ 100,000