Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Stock Subscription Receivable	Additional Paid-in Capital	Accumulated Deficit	Healios	Healios Common Stock	Healios Stock Subscription Receivable	Healios Additional Paid-in Capital	Consolidated entity excluding, related party	Consolidated entity excluding, related party Common Stock	Consolidated entity excluding, related party Additional Paid-in Capital
Preferred stock shares, beginning balance (in shares) at Dec. 31, 2018		0
Common stock, beginning balance (in shares) at Dec. 31, 2018			144,292,739
Beginning balance at Dec. 31, 2018	$ 43,116	$ 0	$ 144		$ 416,014	$ (373,042)
Stock-based compensation	1,090				1,090
Issuance of common stock, net of issuance cost (in shares)												3,825,000
Issuance of common stock, net of issuance cost											$ 5,607	$ 4	$ 5,603
Issuance of common stock under equity compensation plan (in shares)			158,494
Issuance of common stock under equity compensation plan	(69)				(69)
Net comprehensive income (loss)	(12,956)					(12,956)
Preferred stock shares, ending balance (in shares) at Mar. 31, 2019		0
Common stock, ending balance (in shares) at Mar. 31, 2019			148,276,233
Ending balance at Mar. 31, 2019	36,788	$ 0	$ 148		422,638	(385,998)
Preferred stock shares, beginning balance (in shares) at Dec. 31, 2018		0
Common stock, beginning balance (in shares) at Dec. 31, 2018			144,292,739
Beginning balance at Dec. 31, 2018	43,116	$ 0	$ 144		416,014	(373,042)
Net comprehensive income (loss)	(22,644)
Preferred stock shares, ending balance (in shares) at Jun. 30, 2019		0
Common stock, ending balance (in shares) at Jun. 30, 2019			151,777,751
Ending balance at Jun. 30, 2019	33,251	$ 0	$ 152		428,785	(395,686)
Preferred stock shares, beginning balance (in shares) at Mar. 31, 2019		0
Common stock, beginning balance (in shares) at Mar. 31, 2019			148,276,233
Beginning balance at Mar. 31, 2019	36,788	$ 0	$ 148		422,638	(385,998)
Stock-based compensation	1,152				1,152
Issuance of common stock, net of issuance cost (in shares)												3,350,000
Issuance of common stock, net of issuance cost											5,106	$ 4	5,102
Issuance of common stock under equity compensation plan (in shares)			151,518
Issuance of common stock under equity compensation plan	(107)				(107)
Net comprehensive income (loss)	(9,688)					(9,688)
Preferred stock shares, ending balance (in shares) at Jun. 30, 2019		0
Common stock, ending balance (in shares) at Jun. 30, 2019			151,777,751
Ending balance at Jun. 30, 2019	$ 33,251	$ 0	$ 152		428,785	(395,686)
Preferred stock shares, beginning balance (in shares) at Dec. 31, 2019	0	0
Common stock, beginning balance (in shares) at Dec. 31, 2019	159,791,585		159,791,585
Beginning balance at Dec. 31, 2019	$ 23,271	$ 0	$ 160	$ 0	440,735	(417,624)
Stock-based compensation	1,280				1,280
Stock subscription receivable from Healios warrant exercise (in shares)								4,000,000
Stock subscription receivable from Healios warrant exercise							$ 0	$ 4	$ (7,040)	$ 7,036
Issuance of common stock, net of issuance cost (in shares)												6,825,000
Issuance of common stock, net of issuance cost											10,250	$ 7	10,243
Issuance of common stock under equity compensation plan (in shares)			153,504
Issuance of common stock under equity compensation plan	(149)				(149)
Net comprehensive income (loss)	(15,644)					(15,644)
Preferred stock shares, ending balance (in shares) at Mar. 31, 2020		0
Common stock, ending balance (in shares) at Mar. 31, 2020			170,770,089
Ending balance at Mar. 31, 2020	$ 19,008	$ 0	$ 171	(7,040)	459,145	(433,268)
Preferred stock shares, beginning balance (in shares) at Dec. 31, 2019	0	0
Common stock, beginning balance (in shares) at Dec. 31, 2019	159,791,585		159,791,585
Beginning balance at Dec. 31, 2019	$ 23,271	$ 0	$ 160	0	440,735	(417,624)
Net comprehensive income (loss)	$ (34,016)
Preferred stock shares, ending balance (in shares) at Jun. 30, 2020	0	0
Common stock, ending balance (in shares) at Jun. 30, 2020	197,008,562		197,008,562
Ending balance at Jun. 30, 2020	$ 64,178	$ 0	$ 197	0	515,621	(451,640)
Preferred stock shares, beginning balance (in shares) at Mar. 31, 2020		0
Common stock, beginning balance (in shares) at Mar. 31, 2020			170,770,089
Beginning balance at Mar. 31, 2020	19,008	$ 0	$ 171	(7,040)	459,145	(433,268)
Stock-based compensation	2,579				2,579
Stock subscription receivable from Healios warrant exercise							7,040		$ 7,040
Issuance of common stock, net of issuance cost (in shares)								310,526				25,587,500
Issuance of common stock, net of issuance cost							$ 534			$ 534	$ 53,691	$ 26	$ 53,665
Issuance of common stock under equity compensation plan (in shares)			340,447
Issuance of common stock under equity compensation plan	(302)				(302)
Net comprehensive income (loss)	$ (18,372)					(18,372)
Preferred stock shares, ending balance (in shares) at Jun. 30, 2020	0	0
Common stock, ending balance (in shares) at Jun. 30, 2020	197,008,562		197,008,562
Ending balance at Jun. 30, 2020	$ 64,178	$ 0	$ 197	$ 0	$ 515,621	$ (451,640)