Enterprise-wide Disclosures (Details) - USD ($) $ in Thousands		3 Months Ended									12 Months Ended
		Dec. 31, 2016		Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016		Dec. 31, 2015	Dec. 31, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues		$ 1,103		$ 1,441	$ 1,171	$ 1,848	$ 1,306	$ 1,874	$ 1,749	$ 1,000	$ 5,923		$ 7,036	$ 5,244
Long-lived assets		5,529	[1]				7,539				5,529	[1]	7,539
Domestic [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues											4,497		5,976	3,586
Long-lived assets		3,418	[1]				7,132				3,418	[1]	7,132
Foreign [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets		$ 2,111	[1]				$ 407				2,111	[1]	407
Asia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues											$ 1,426		$ 1,060	$ 1,658
CIRM Grant Income [Member]
Revenue, Major Customer [Line Items]
Percentage of total revenues											38.00%		42.70%	19.70%
N I H Grant Income [Member]
Revenue, Major Customer [Line Items]
Percentage of total revenues											0.00%		6.50%	12.50%
IIA (formerly OCS) grant income (Cell Cure, Israel) [Member]
Revenue, Major Customer [Line Items]
Percentage of total revenues											24.00%		14.40%	31.30%
Subscription, Advertising and Other (various customers) [Member]
Revenue, Major Customer [Line Items]
Percentage of total revenues	[2]										35.00%		29.40%	32.50%
Other [Member]
Revenue, Major Customer [Line Items]
Percentage of total revenues	[2]										3.00%		7.00%	4.00%
LifeMap Sciences, Ltd. [Member]
Revenue, Major Customer [Line Items]
Payment received from research project											$ 972		$ 1,357
Advertising revenue											668		679
Revenues of royalty and commission fees											$ 304		$ 678

[1] Reflects the effect of the Asterias Deconsolidation.

[2] No individual customer greater than 5% of total revenues.