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Stockholders' Equity - Common Stock (Details) - shares | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Class of Stock [Line Items] |  |
Number of shares reserved for future issuance (in shares) | 9,199,512 | 6,869,189
Warrants and share-based payment awards |  |
Class of Stock [Line Items] |  |
Number of shares reserved for future issuance (in shares) | 9,199,512 | 6,869,189
Share-based payments | Stock options |  |
Class of Stock [Line Items] |  |
Number of shares reserved for future issuance (in shares) | 8,342,429 | 6,112,948
Share-based payments | Restricted stock units |  |
Class of Stock [Line Items] |  |
Number of shares reserved for future issuance (in shares) | 817,609 | 716,767
Warrants |  |
Class of Stock [Line Items] |  |
Number of shares reserved for future issuance (in shares) | 39,474 | 39,474

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