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Consolidated Statement of Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Issuance cost of common stock | $ 1,148 | $ 3,874 |
Series E Preferred Stock [Member] |  |  |
Issuance cost of convertible preferred Stock |  |  | $ 214

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