Organization, Basis of Presentation, and Summary of Select Significant Accounting Policies (Details) (USD $)	3 Months Ended			9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011	Sep. 30, 2012		Sep. 30, 2011	Dec. 31, 2011	Apr. 29, 2009
Noncontrolling Interest [Line Items]
Amount of CIRM grant award								$ 4,721,706
Grants revenue	441,630		746,426	1,518,086		1,605,612
Trade accounts receivable	891,000			891,000			353,000
Grants receivable	38,000			38,000			630,000
Allowance for doubtful accounts	100,000			100,000			100,000
Property, Plant and Equipment [Line Items]
Foreign currency translation loss	15,777		(696,661)	74,635		901,881
Foreign currency transaction gain (loss)				39,930		90,774
Income tax penalties and interest accrued	0			0			0
Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from computation of diluted loss per share (in shares)	556,613		636,613	556,613		636,613
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from computation of diluted loss per share (in shares)	3,492,135		3,249,647	3,492,135		3,249,647
Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Equipment useful life				36 months
Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Equipment useful life				120 months
ReCyte Therapeutics, Inc. [Member]
Noncontrolling Interest [Line Items]
BioTime ownership (in hundredths)	95.15%			95.15%
Country				USA
OncoCyte Corporation [Member]
Noncontrolling Interest [Line Items]
BioTime ownership (in hundredths)	75.30%			75.30%
Country				USA
OrthoCyte Corporation [Member]
Noncontrolling Interest [Line Items]
BioTime ownership (in hundredths)	100.00%			100.00%
Country				USA
ES Cell International Pte., Ltd. [Member]
Noncontrolling Interest [Line Items]
BioTime ownership (in hundredths)	100.00%			100.00%
Country				Singapore
BioTime Asia, Limited [Member]
Noncontrolling Interest [Line Items]
BioTime ownership (in hundredths)	81.00%			81.00%
Country				Hong Kong
Cell Cure Neurosciences, Ltd. [Member]
Noncontrolling Interest [Line Items]
Grants revenue	168,923			416,857
BioTime ownership (in hundredths)	53.60%	[1]		53.60%	[1]
Country				Israel
BioTime ownership after issuing additional shares (in hundredths)	62.60%			62.60%
LifeMap Sciences, Inc. [Member]
Noncontrolling Interest [Line Items]
BioTime ownership (in hundredths)	77.10%	[2]		77.10%	[2]
Country				USA
BioTime ownership after issuing additional shares (in hundredths)	73.20%			73.20%
LifeMap Sciences, Ltd. [Member]
Noncontrolling Interest [Line Items]
Grants revenue	7,692			15,587
BioTime ownership (in hundredths)		[3]			[3]
Country				Israel
BioTime Acquisition Corporation [Member]
Noncontrolling Interest [Line Items]
BioTime ownership (in hundredths)	96.70%			96.70%
Country				USA
California Institute of Regenerative Medicine [Member]
Noncontrolling Interest [Line Items]
Grants revenue	261,776			1,047,107
National Institutes of Health [Member]
Noncontrolling Interest [Line Items]
Grants revenue	$ 3,239			$ 38,535

[1] Cell Cure Neurosciences has agreed to issue additional ordinary shares to BioTime in exchange for BioTime common shares which will increase BioTime's ownership, directly and through ESI, to approximately 62.6%. See Note 11.

[2] LifeMap Sciences, Inc. has agreed to issue additional shares of its common stock to certain investors which will reduce BioTime's ownership 73.2%. See Note 9.

[3] LifeMap Sciences, Ltd. is a wholly-owned subsidiary of LifeMap Sciences, Inc.