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CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED SHARES AND STOCKHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Payment of offering costs | $ 248 | $ 953
Series C Preferred Stock [Member] | Maximum [Member] |  |
Payment of offering costs |  | 100
Series D Preferred Stock [Member] |  |
Payments of financing costs |  | 200
Common Stock [Member] |  |
Payment of offering costs |  | $ 700
Common Stock [Member] | Pfizer Purchase Agreement [Member] |  |
Payments of financing costs | 200 |
Premium on issued of common stock | $ 12,500 |

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- Definition The cash outflow for loan and debt issuance costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585 + Details
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- Definition The cash outflow for cost incurred directly with the issuance of an equity security. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585 + Details
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