Enterprise-Wide Disclosures - Schedule of Geographic Area Information (Details) - USD ($) $ in Thousands		3 Months Ended										12 Months Ended
		Dec. 31, 2017		Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016		Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Total revenues		$ 945		$ 1,636	$ 376	$ 333	$ 1,103		$ 1,441	$ 1,171	$ 1,848	$ 3,458		$ 5,923		$ 7,036
Long-lived assets		5,533	[1]				5,529	[2]				5,533	[1]	5,529	[2]
United States [Member]
Total revenues												1,651		4,497		5,976
Foreign [Member]
Total revenues	[3]											1,807		1,426		$ 1,060
Long-lived assets		2,787	[1]				2,111	[2]				2,787	[1]	2,111	[2]
Domestic [Member]
Long-lived assets		$ 2,746	[1]				$ 3,418	[2]				$ 2,746	[1]	$ 3,418	[2]

[1] Reflects the effect of the OncoCyte Deconsolidation.

[2] Reflects the effect of the Asterias Deconsolidation.

[3] Foreign revenues are primarily earned in Israel.