Refers to number of investors.

No definition available.

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- Definition

The number of shares sold by third parities during the period reported.

+ References

No definition available.

+ Details

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- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The cash inflow associated with the sale of equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26853-111562

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Balance Type:	na
Period Type:	duration

- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
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- Details

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Sales of BioTime Common Shares by Subsidiaries (Details) (USD $)	1 Months Ended	3 Months Ended
	Jun. 30, 2014	Mar. 31, 2015 Investor
Related Party Transaction [Line Items]
Number of shares sold (in shares)	5,000,000btx_SharesSoldByThirdParty
Asterias Biotherapeutics [Member] \| BioTime Common Stock [Member]
Related Party Transaction [Line Items]
Number of shares sold (in shares)		5,000,000
Number of investors		2
Proceeds from sale of BioTime stock		$ 12,500,000
Asterias Biotherapeutics [Member] \| Asterias Series B Common Stock [Member]
Related Party Transaction [Line Items]
Number of shares purchased (in shares)		5,000,000
Broadwood Partners, LP [Member] \| BioTime Common Stock [Member]
Related Party Transaction [Line Items]
Number of shares purchased (in shares)		1,000,000
Broadwood Partners, LP [Member] \| Asterias Warrants [Member]
Related Party Transaction [Line Items]
Number of warrants issued (in shares)		1,000,000
George Karfunkel [Member] \| BioTime Common Stock [Member]
Related Party Transaction [Line Items]
Number of shares purchased (in shares)		4,000,000
George Karfunkel [Member] \| Asterias Warrants [Member]
Related Party Transaction [Line Items]
Number of warrants issued (in shares)		4,000,000