Common stock held in investment.

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Exchange for cash.

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Exchange of shares.

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Fair value calculation, description.

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Fair value of Equity method investment, shares.

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Upfront payment received.

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Number of shares of equity interests issued or issuable to acquire entity.

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The net effect on income before taxes of the amortization and accretion of premiums, discounts and intangible assets in the year of acquisition, when the assets of the acquired institution exceed 10 percent of the consolidated assets at the end of the most recent period.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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This element represents the aggregate cost of investments accounted for under the equity method of accounting.

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Amount of expense (income) related to adjustment to fair value of warrant liability.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Price of a single share of a number of saleable stocks of a company.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.

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Expiration date of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in CCYY-MM-DD format.

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Asterias Merger (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended		3 Months Ended	6 Months Ended
	Mar. 31, 2019	Mar. 08, 2019	Mar. 08, 2019	Apr. 30, 2019	Sep. 30, 2018	Jun. 30, 2019	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	May 13, 2016
Closing price of common stock						$ 133,387	$ 133,387		$ 93,840
Number of warrants issued to purchase of common stock										2,813,159
Fair value of warrants				$ 372			(271)	$ (351)
Common stock held in investment		2,621,811	2,621,811
Share price, per share		$ 1.31	$ 1.31						$ 0.62
Fair value of equity method investment, shares	21,700,000
Fair value of equity method investment, value		$ 20,200	$ 20,200						$ 13,500
Fair value calculation, description		The fair value of the Asterias shares was approximately $20.2 million as of March 8, 2019, the closing date of the Asterias Merger, based on $0.93 per share, which was calculated by multiplying (a) $1.31, the closing price of BioTime common stock on such date by (b) the Merger Exchange Ratio.
General and Administrative [Member]
Acquisition related costs						$ 900	$ 4,400
Common Stock [Member]
Number of warrants issued to purchase of common stock										2,959,559
Exercise price										$ 4.37
Warrant term										5 years
Warrant expiration date										May 13, 2021
BioTime Warrants [Member]
Exercise price						$ 6.15	$ 6.15
Warrant expiration date						May 13, 2021	May 13, 2021
Fair value of warrants	$ 495
AST Clinical Program [Member]
Identifiable intangible asset acquired		$ 46,500
Royalty Contracts [Member]
Useful life of asset							5 years
In Process Research and Development [Member]
Identifiable intangible asset acquired		31,700
Regenerative Medicine [Member]
Identifiable intangible asset acquired		$ 14,800
December 31, 2018 to March 8, 2019 [Member]
Unrealized loss							$ 6,700
December 31, 2017 to June 30, 2018 [Member]
Unrealized loss								$ 19,600
December 31, 2017 to June 30, 2018 [Member] \| Maximum [Member]
Share price, per share								$ 2.25
December 31, 2017 to June 30, 2018 [Member] \| Minimum [Member]
Share price, per share								$ 1.35
Parent Company [Member]
Number of warrants issued to purchase of common stock						1,089,900	1,089,900
Fair value of warrants				$ 332
Exchange of shares				251,835
Exchange for cash				$ 40
Asterias [Member]
Upfront payment received					$ 1,000
Estimated purchase price					$ 200
Merger Consideration [Member] \| Parent Company [Member]
Stock-for-stock transaction		24,695,898	24,695,898
Closing price of common stock		$ 32,400	$ 32,400
Merger Consideration [Member] \| Asterias [Member]
Stock-for-stock transaction		0.71	0.71
Merger Consideration [Member] \| Asterias [Member] \| Restricted Stock [Member]
Stock-for-stock transaction		58,085	58,085