Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Noncontrolling Interest [Member]	Accumulated Other Comprehensive Income [Member]	Total
Beginning balance at Dec. 31, 2018	$ 4	$ 81,499	$ (74,054)	$ 784	$ (2)	$ 8,231
Beginning balance, shares at Dec. 31, 2018	35,830,000
Issuance of common stock from exercise of warrants		4,500				4,500
Issuance of common stock from exercise of warrants, shares	1,800,000
Issuance of common stock to Juvenescence		56				56
Issuance of common stock to Juvenescence, shares	19,000
Issuance of warrants to Juvenescence		236				236
Stock-based compensation		1,907				1,907
Lapse of subsidiary options		155		(155)
Foreign currency translation adjustment					71	71
Net loss			(12,154)	(230)		(12,384)
Ending balance at Dec. 31, 2019	$ 4	88,353	(86,208)	399	69	2,617
Ending balance, shares at Dec. 31, 2019	37,649,000
Issuance of common stock to Juvenescence		37				37
Issuance of common stock to Juvenescence, shares	29,000
Issuance of common stock upon vesting of restricted stock units, net of shares retired to pay employee's taxes		(9)				(9)
Issuance of common stock upon vesting of restricted stock units, net of shares retired to pay employee's taxes, shares	13,000
Issuance of warrants to Juvenescence		1,640				1,640
Stock-based compensation		933				933
Issuance of subsidiary common stock - LifeMap Sciences				288		288
Transactions with noncontrolling interests - LifeMap Sciences and ReCyte		856		(856)
Foreign currency translation adjustment					74	74
Net loss			(10,865)	(111)		(10,976)
Ending balance at Dec. 31, 2020	$ 4	$ 91,810	$ (97,073)	$ (280)	$ 143	$ (5,396)
Ending balance, shares at Dec. 31, 2020	37,691,000