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Stockholders' Equity - Warrants (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Class of Stock [Line Items] |  |
Warrant exercise price (in dollars per share) |  | $ 2.25
Warrant liability | $ 1 | $ 7
Change in fair value of warrants | $ (6) | $ (2,400)
Series U Warrants [Member] |  |
Class of Stock [Line Items] |  |
Common stock issued (in shares) | 3,450,000 |
Sale of Stock, Price Per Share | $ 5.00 |
Warrants expected term | 5 years |
Representative Warrants [Member] |  |
Class of Stock [Line Items] |  |
Number of securities called by warrant or right | 75,000 |
Warrant exercise price (in dollars per share) | $ 6.25 |
Warrant exercise price decrease |  | $ 2.81
Common Stock [Member] |  |
Class of Stock [Line Items] |  |
Common stock issued (in shares) | 7,864,379 | 2,150,113
Warrants expected term | 5 years |
Outstanding Warrants [Member] |  |
Class of Stock [Line Items] |  |
Warrant liability |  | $ 4,500
Change in fair value of warrants |  | $ 700
Outstanding Warrants [Member] | Series U Warrants [Member] |  |
Class of Stock [Line Items] |  |
Number of securities called by warrant or right |  | 3,447,500
Class of warrant outstanding | 2,141,000 |
Number of warrant classified as equity | 2,138,500 |
Number of warrants exercised | 2,141,000 |
Common Class A [Member] |  |
Class of Stock [Line Items] |  |
Common stock issued (in shares) | 289,000 |
Common Class B [Member] |  |
Class of Stock [Line Items] |  |
Number of securities called by warrant or right | 2,711,000 |

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