Organization, Basis of Presentation and Liquidity (Details) - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Noncontrolling Interest [Line Items]
Accumulated deficit		$ (202,055)	$ (182,190)
Shareholders' equity		64,951	62,723
Cash and cash equivalents		31,465	$ 29,487	$ 15,722	$ 5,495
Parent [Member]
Noncontrolling Interest [Line Items]
Accumulated deficit		(202,100)
Working capital		27,800
Shareholders' equity		65,000
Cash and cash equivalents		$ 31,500
Asterias Biotherapeutics, Inc. [Member]
Noncontrolling Interest [Line Items]
BioTime Ownership (in hundredths)		58.00%
Cell Cure Neurosciences, Ltd. [Member]
Noncontrolling Interest [Line Items]
BioTime Ownership (in hundredths)	[1]	62.50%
ES Cell International Pte., Ltd. [Member]
Noncontrolling Interest [Line Items]
BioTime Ownership (in hundredths)		100.00%
LifeMap Sciences, Inc. [Member]
Noncontrolling Interest [Line Items]
BioTime Ownership (in hundredths)		77.10%
LifeMap Sciences, Ltd. [Member]
Noncontrolling Interest [Line Items]
BioTime Ownership (in hundredths)	[2]	0.00%
LifeMap Solutions, Inc. [Member]
Noncontrolling Interest [Line Items]
BioTime Ownership (in hundredths)	[2]	0.00%
OncoCyte Corporation [Member]
Noncontrolling Interest [Line Items]
BioTime Ownership (in hundredths)		71.70%
OrthoCyte Corporation [Member]
Noncontrolling Interest [Line Items]
BioTime Ownership (in hundredths)	[3]	100.00%
ReCyte Therapeutics, Inc. [Member]
Noncontrolling Interest [Line Items]
BioTime Ownership (in hundredths)		94.80%

[1] Includes shares owned by BioTime, Asterias, and ESI.

[2] LifeMap Sciences, Ltd. and LifeMap Solutions, Inc. are wholly-owned subsidiaries of LifeMap Sciences, Inc.

[3] Includes shares owned by BioTime and Asterias.