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Condensed Statements of Stockholders' Equity (unaudited) (Parenthetical) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended
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Mar. 31, 2021 | Dec. 31, 2021 | Dec. 31, 2020
Series A Redeemable Convertible Preferred Stock |  |  |
Stock issuance costs |  | $ 4 | $ 200
Series B Redeemable Convertible Preferred Stock |  |  |
Stock issuance costs | $ 200 | $ 226 |

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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 -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-15 + Details
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