Property, Plant and Equipment, Net - Schedule of Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2017	[1]	Dec. 31, 2016	[2]
Property, Plant and Equipment [Line Items]
Accumulated depreciation and amortization	$ (3,156)		$ (2,980)
Property, plant and equipment, net	5,533		5,529
Equipment, Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	4,255		4,718
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 4,434		$ 3,791

[1] Reflects the effect of the OncoCyte Deconsolidation.

[2] Reflects the effect of the Asterias Deconsolidation