Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands | Total | Preferred Stock | Common Stock | Stock Subscription Receivable | Additional Paid-in Capital | Accumulated Deficit | Consolidated entity excluding, related party | Consolidated entity excluding, related partyCommon Stock | Consolidated entity excluding, related partyAdditional Paid-in Capital | Healios | HealiosCommon Stock | HealiosStock Subscription Receivable | HealiosAdditional Paid-in Capital |
Preferred stock shares, beginning balance (in shares) at Dec. 31, 2019 | | 0 | | | | | | | | | | | |
Beginning balance at Dec. 31, 2019 | $ 23,271 | $ 0 | $ 160 | $ 0 | $ 440,735 | $ (417,624) | | | | | | | |
Common stock, beginning balance (in shares) at Dec. 31, 2019 | | | 159,791,585 | | | | | | | | | | |
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 (in shares) | | | 6,825,000 | | | | | | | | | | |
Issuance of common stock | 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 loss | (15,644) | | | | | (15,644) | | | | | | | |
Preferred stock shares, ending balance (in shares) at Mar. 31, 2020 | | 0 | | | | | | | | | | | |
Ending balance at Mar. 31, 2020 | 19,008 | $ 0 | $ 171 | (7,040) | 459,145 | (433,268) | | | | | | | |
Common stock, ending balance (in shares) at Mar. 31, 2020 | | | 170,770,089 | | | | | | | | | | |
Preferred stock shares, beginning balance (in shares) at Dec. 31, 2019 | | 0 | | | | | | | | | | | |
Beginning balance at Dec. 31, 2019 | 23,271 | $ 0 | $ 160 | 0 | 440,735 | (417,624) | | | | | | | |
Common stock, beginning balance (in shares) at Dec. 31, 2019 | | | 159,791,585 | | | | | | | | | | |
Net comprehensive loss | (34,016) | | | | | | | | | | | | |
Preferred stock shares, ending balance (in shares) at Jun. 30, 2020 | | 0 | | | | | | | | | | | |
Ending balance at Jun. 30, 2020 | 64,178 | $ 0 | $ 197 | 0 | 515,621 | (451,640) | | | | | | | |
Common stock, ending balance (in shares) at Jun. 30, 2020 | | | 197,008,562 | | | | | | | | | | |
Preferred stock shares, beginning balance (in shares) at Mar. 31, 2020 | | 0 | | | | | | | | | | | |
Beginning balance at Mar. 31, 2020 | 19,008 | $ 0 | $ 171 | (7,040) | 459,145 | (433,268) | | | | | | | |
Common stock, beginning balance (in shares) at Mar. 31, 2020 | | | 170,770,089 | | | | | | | | | | |
Stock-based compensation | 2,579 | | | | 2,579 | | | | | | | | |
Stock subscription receivable from Healios warrant exercise | | | | | | | | | | 7,040 | | $ 7,040 | |
Issuance of common stock (in shares) | | | | | | | | 25,587,500 | | | 310,526 | | |
Issuance of common stock | | | | | | | $ 53,691 | $ 26 | $ 53,665 | $ 534 | | | $ 534 |
Issuance of common stock under equity compensation plan (in shares) | | | 340,447 | | | | | | | | | | |
Issuance of common stock under equity compensation plan | (302) | | | | (302) | | | | | | | | |
Net comprehensive loss | (18,372) | | | | | (18,372) | | | | | | | |
Preferred stock shares, ending balance (in shares) at Jun. 30, 2020 | | 0 | | | | | | | | | | | |
Ending balance at Jun. 30, 2020 | $ 64,178 | $ 0 | $ 197 | $ 0 | 515,621 | (451,640) | | | | | | | |
Common stock, ending balance (in shares) at Jun. 30, 2020 | | | 197,008,562 | | | | | | | | | | |
Preferred stock shares, beginning balance (in shares) at Dec. 31, 2020 | 0 | 0 | | | | | | | | | | | |
Beginning balance at Dec. 31, 2020 | $ 31,362 | $ 0 | $ 202 | | 527,549 | (496,389) | | | | | | | |
Common stock, beginning balance (in shares) at Dec. 31, 2020 | 201,973,582 | | 201,973,582 | | | | | | | | | | |
Stock-based compensation | $ 3,903 | | | | 3,903 | | | | | | | | |
Issuance of common stock (in shares) | | | 15,200,000 | | | | | | | | | | |
Issuance of common stock | 30,495 | | $ 15 | | 30,480 | | | | | | | | |
Issuance of common stock under equity compensation plan (in shares) | | | 437,925 | | | | | | | | | | |
Issuance of common stock under equity compensation plan | (611) | | $ 1 | | (612) | | | | | | | | |
Net comprehensive loss | (26,468) | | | | | (26,468) | | | | | | | |
Preferred stock shares, ending balance (in shares) at Mar. 31, 2021 | | 0 | | | | | | | | | | | |
Ending balance at Mar. 31, 2021 | $ 38,681 | $ 0 | $ 218 | | 561,320 | (522,857) | | | | | | | |
Common stock, ending balance (in shares) at Mar. 31, 2021 | | | 217,611,507 | | | | | | | | | | |
Preferred stock shares, beginning balance (in shares) at Dec. 31, 2020 | 0 | 0 | | | | | | | | | | | |
Beginning balance at Dec. 31, 2020 | $ 31,362 | $ 0 | $ 202 | | 527,549 | (496,389) | | | | | | | |
Common stock, beginning balance (in shares) at Dec. 31, 2020 | 201,973,582 | | 201,973,582 | | | | | | | | | | |
Net comprehensive loss | $ (49,067) | | | | | | | | | | | | |
Preferred stock shares, ending balance (in shares) at Jun. 30, 2021 | 0 | 0 | | | | | | | | | | | |
Ending balance at Jun. 30, 2021 | $ 31,046 | $ 0 | $ 226 | | 576,276 | (545,456) | | | | | | | |
Common stock, ending balance (in shares) at Jun. 30, 2021 | 226,255,093 | | 226,255,093 | | | | | | | | | | |
Preferred stock shares, beginning balance (in shares) at Mar. 31, 2021 | | 0 | | | | | | | | | | | |
Beginning balance at Mar. 31, 2021 | $ 38,681 | $ 0 | $ 218 | | 561,320 | (522,857) | | | | | | | |
Common stock, beginning balance (in shares) at Mar. 31, 2021 | | | 217,611,507 | | | | | | | | | | |
Stock-based compensation | 1,788 | | | | 1,788 | | | | | | | | |
Issuance of common stock (in shares) | | | | | | | | 8,500,000 | | | | | |
Issuance of common stock | | | | | | | $ 13,292 | $ 8 | $ 13,284 | | | | |
Issuance of common stock under equity compensation plan (in shares) | | | 143,586 | | | | | | | | | | |
Issuance of common stock under equity compensation plan | (116) | | | | (116) | | | | | | | | |
Net comprehensive loss | $ (22,599) | | | | | (22,599) | | | | | | | |
Preferred stock shares, ending balance (in shares) at Jun. 30, 2021 | 0 | 0 | | | | | | | | | | | |
Ending balance at Jun. 30, 2021 | $ 31,046 | $ 0 | $ 226 | | $ 576,276 | $ (545,456) | | | | | | | |
Common stock, ending balance (in shares) at Jun. 30, 2021 | 226,255,093 | | 226,255,093 | | | | | | | | | | |