Subsequent Events (Details) (USD $)	12 Months Ended													0 Months Ended			1 Months Ended			0 Months Ended			0 Months Ended	3 Months Ended	0 Months Ended	12 Months Ended		0 Months Ended			1 Months Ended		12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	May 01, 2013	Mar. 14, 2013	Dec. 31, 2012 OrthoCyte Corporation [Member]	Jan. 29, 2013 Cell Cure Neurosciences, Ltd. [Member]	Dec. 31, 2012 Cell Cure Neurosciences, Ltd. [Member]		Apr. 10, 2013 BioTime Acquisition Corporation [Member]	Dec. 31, 2012 BioTime Acquisition Corporation [Member]		Apr. 10, 2013 Geron [Member]	Apr. 10, 2013 Subsequent Event [Member]	Jan. 08, 2013 Subsequent Event [Member] sqft	Jan. 04, 2013 Subsequent Event [Member]	Jan. 31, 2013 Subsequent Event [Member]	May 01, 2013 Subsequent Event [Member]	Jan. 29, 2013 Subsequent Event [Member]	Jan. 04, 2013 Subsequent Event [Member] Common Class B [Member]	Apr. 10, 2013 Subsequent Event [Member] Common Class B [Member]	Jan. 04, 2013 Subsequent Event [Member] OrthoCyte Corporation [Member]	Mar. 14, 2013 Subsequent Event [Member] ReCyte [Member]	Jun. 30, 2013 Subsequent Event [Member] ReCyte [Member]	Jan. 29, 2013 Subsequent Event [Member] Cell Cure Neurosciences, Ltd. [Member]	Dec. 31, 2012 Subsequent Event [Member] Cell Cure Neurosciences, Ltd. [Member]	Jan. 04, 2013 Subsequent Event [Member] Cell Cure Neurosciences, Ltd. [Member]	Apr. 10, 2013 Subsequent Event [Member] BioTime Acquisition Corporation [Member]	Jan. 29, 2013 Subsequent Event [Member] BioTime Acquisition Corporation [Member]	Jan. 04, 2013 Subsequent Event [Member] BioTime Acquisition Corporation [Member]	Apr. 30, 2013 Subsequent Event [Member] BioTime Acquisition Corporation [Member]	Jan. 31, 2013 Subsequent Event [Member] BioTime Acquisition Corporation [Member]	Dec. 31, 2013 Subsequent Event [Member] BioTime Acquisition Corporation [Member]	May 01, 2013 Subsequent Event [Member] BioTime Acquisition Corporation [Member]	Apr. 10, 2013 Subsequent Event [Member] BioTime Acquisition Corporation [Member] Common Class B [Member]	Apr. 10, 2013 Subsequent Event [Member] Geron [Member]
Asset Contribution Agreement [Abstract]
Percentage of subsidiary stock contributed (in hundredths)																						10.00%					6.00%
Proceeds from issuance of common shares to a private investor	$ 1,131,279	$ 0	$ 0																	$ 5,000,000			$ 125,000										$ 11,306,430
Stock Purchase Agreement, proceeds from issuance of common stock																							250,000	125,000
Stock issued during period (in shares)	314,386															1,350,000				2,136,000			40,584							8,902,077	810,000	540,000
Stock Purchase Agreement, shares to be issued (in shares)																							81,169	40,585
Number of warrants issued (in shares)														350,000		650,000				350,000	389,998									8,000,000		259,999			3,150,000
Amount of Contribution funded Under Tranche One																	2,000,000
Amount Of Contribution Funded Under Tranche Two														3,000,000
Amount of contribution from investor																5,000,000														5,000,000
Number of tranches																														2
Exercise price of warrant (in dollars per share)														$ 5.00
Number of shares held (in shares)														2,136,000														21,773,340								6,537,779
Bio Time ownership (in hundredths)						100.00%	62.60%	53.60%	[1]	71.60%	96.70%	[2]													62.60%			71.60%
Geron ownership (in hundredths)													21.40%
Percentage of equity interest owned by private investor (in hundredths)														7.00%
Warrant expiration term														3 years
Agreement Termination Fees																												1,800,000
Number of shareholders participating in Stock Purchase Agreement					1
Leases [Abstract]
Area of space (in sq. feet)															24,080
Lease term															3 years
Rent expenses	1,178,840	1,058,170	656,883												31,786
Shares issued in connection with lease (in shares)															242,726
Lease and rental expense on failure to register shares															38,528
Threshold limit to register shares															120 days
Cell Cure Neurosciences Investment [Abstract]
Number of shares purchased (in shares)																									87,456
Shares issued in exchange of shares purchase (in shares)																													906,735
Percentage of ownership interest in subsidiary (in hundredths)						100.00%	62.60%	53.60%	[1]	71.60%	96.70%	[2]													62.60%			71.60%
Average market price (in dollars per share)																									$ 3.86				$ 4.46
Number of trading days prior certain period																										10 years
Value of common shares issued to be maintained after additional issuance																																		3,500,000
Percentage by which share price increase decrease (in hundredths)																		15.00%
Minimum market price per share multiplied (in dollars per share)				$ 3.86
Threshold limit on number of shares issued (in hundredths)																									33.00%				33.00%
Proceeds from issuance of common shares	1,131,279	0	0																	5,000,000			125,000										11,306,430
Number of shares issued through open market (in shares)	78,598																																2,537,051
Weighted average purchase price of shares (in dollars per share)																									$ 3.86				$ 4.46
Stock Purchase Agreement, price per share																							$ 3.08
Amount of controlled equity offering facility																			$ 25,000,000

[1] In January 2013 Cell Cure Neurosciences issued additional ordinary shares to BioTime in exchange for BioTime common shares which increased BioTime's ownership, directly and through ESI, to approximately 62.6%. See Note 23.

[2] BioTime expects that its percentage ownership will be reduced to approximately 71.6% after BAC issues common stock to BioTime and Geron Corporation pursuant to an Asset Contribution Agreement and sells common stock and warrants to a private investor for cash in a related transaction.