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Stockholders' Equity (Details) - USD ($) |  |  |  |  |  | 1 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 27, 2021 | Nov. 16, 2020 | Oct. 15, 2018 | Oct. 10, 2018 | Sep. 11, 2017 | Sep. 30, 2021 | Feb. 28, 2021 | Dec. 31, 2020 | Oct. 31, 2018 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2017 | Mar. 29, 2021 | Dec. 31, 2018 | Aug. 05, 2016
Proceeds from Issuance or Sale of Equity |  |  | $ 18,600,000 |  |  |  |  |  |  |  |  |  |  |  |
Preferred Stock, Par or Stated Value Per Share |  | $ 0.001 |  |  |  |  |  | $ 1,000 |  | $ 1,000 | $ 1,000 |  |  |  |
Exercise price per warrant |  | 1.38 | $ 1.38 |  |  |  |  |  |  |  |  |  |  |  |
Effect of Warrant exercise price adjustment |  |  |  |  |  |  |  | $ 900,000 |  | $ 0 | $ 880,000 |  |  |  |
Preferred Stock, Convertible, Conversion Price, Decrease | $ 1.50 | $ 0.69 |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock issued upon conversion |  |  |  |  |  |  | 8,996,768 |  |  |  |  |  |  |  |
Preferred Stock, Shares Outstanding |  |  |  |  |  |  |  | 3,973 |  | 0 | 3,973 |  |  |  |
Estimated fair value of inducement consideration |  |  |  |  |  |  |  |  |  | $ 7,400,000 |  |  |  |  |
Proceeds from Issuance of Common Stock |  |  |  |  |  |  |  |  |  | $ 65,960,000 | $ 3,359,000 |  |  |  |
Preferred Stock Shares Converted |  | 1.38 |  |  |  |  |  |  |  | 3,973 | 3,665 |  |  |  |
Proceeds from Stock Options Exercised |  |  |  |  |  |  |  |  |  | $ 0 | $ 0 |  |  |  |
Stock Purchase Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Common Stock |  |  |  |  |  |  |  |  |  | 66,000,000.0 |  |  |  |  |
Sale of Stock, Consideration Received on Transaction |  |  |  |  |  |  |  |  |  | $ 78,700,000 |  |  |  |  |
Over-Allotment Option [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues |  | 2,428,825 |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right, Number of Securities Called by Warrants or Rights |  | 2,428,825 |  |  |  |  |  |  |  |  |  |  |  |  |
Issue of warrants to purchase common stock |  | 1,807,826 |  |  |  |  |  |  |  |  |  |  |  |  |
Fbr Capital Markets Co [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues |  |  |  |  |  |  |  |  |  | 9,300,000 |  |  |  |  |
Brokerage Commission percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.00%
Proceeds from Issuance of Common Stock for Exclusive Channel Collaboration Agreement |  |  |  |  |  |  |  |  |  |  | 3,400,000 |  |  |  |
Series A Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred Stock Conversion Price Per Share |  |  |  |  | $ 0.54 |  |  |  |  |  |  |  |  |  |
Effect of Warrant exercise price adjustment |  |  |  |  |  |  |  |  |  |  | 1,000,000.0 |  |  |  |
Preferred Stock Redemption Discount |  |  |  |  |  |  |  |  |  | $ 100,000 |  |  |  | $ 6,900,000 |
Preferred Stock, Dividend Rate, Percentage |  |  |  |  | 2.00% |  |  |  |  |  |  | 2.00% |  |  |
Preferred Stock, Convertible, Conversion Price, Increase |  |  |  |  | $ 18.90 | $ 18.90 |  |  |  |  |  |  |  |  |
Preferred Stock, Convertible, Conversion Price, Decrease | $ 1.50 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible Preferred Stock, Terms of Conversion |  |  |  |  | (i) a 19.99% blocker provision to comply with NYSE American Listing Rules, (ii) if so elected by the Investor, a 4.99% blocker provision that will prohibit beneficial ownership of more than 4.99% of the outstanding shares of the Company’s common stock or voting power at any time, and (iii) applicable regulatory restrictions. |  |  |  |  |  |  |  |  |  |
Preferred stock accrued dividends |  |  |  |  |  |  |  |  |  | 24,000 | 254,000 |  |  |  |
Maximum percentage | 4.99% |  |  |  |  |  |  |  |  |  |  |  | 9.99% |  |
Accretion of Preferred Stock Deemed Dividend |  |  |  |  |  |  |  |  |  |  | 300,000 |  |  |  |
Preferred Stock, Redemption Terms |  |  |  |  | (i) the VWAP (as defined in the Certificate of Designation) for at least 20 trading days in any 30 trading day period is greater than $70.00, subject to adjustment in the case of stock split, stock dividends or the like the Company has the right, after providing notice not less than 6 months prior to the redemption date, to redeem, in whole or in part, on a pro rata basis from all holders thereof based on the number of shares of Series A Preferred Stock then held, the outstanding Series A Preferred Stock, for cash, at a redemption price per share of Series A Preferred Stock of $7,875.00, subject to appropriate adjustment in the event of any stock dividend, stock split, combination or other similar recapitalization with respect to the Series A Convertible Preferred Stock or (ii) the five year anniversary of the issue date, the Company shall have the right to redeem, in whole or in part, on a pro rata basis from all holders thereof based on the number of shares of Series A Convertible Preferred Stock then held, the outstanding Series A Preferred Stock, for cash, at a redemption price per share equal to the Liquidation Value. |  |  |  |  |  |  |  |  |  |
Series A Preferred Stock [Member] | Private Placement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues |  |  |  |  | 120,000 |  | 120,000 |  |  |  |  |  |  |  |
Preferred Stock, Par or Stated Value Per Share |  |  |  |  | $ 0.001 |  |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Convertible Preferred Stock |  |  |  |  | $ 12,000,000 |  |  |  |  |  |  |  |  |  |
Sale of Stock, Consideration Received Per Transaction |  |  |  |  | $ 100 |  |  |  |  |  |  |  |  |  |
Series B Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares Issued, Price Per Share |  |  | $ 1.15 |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Value, Issued for Services |  |  | $ 1,000 |  |  |  |  |  |  |  |  |  |  |  |
Preferred Stock, Par or Stated Value Per Share |  |  | $ 1,000 |  |  |  |  |  |  |  |  |  |  |  |
Preferred Stock Conversion Price Per Share |  |  | $ 1.15 |  |  |  |  |  |  |  |  |  |  |  |
Conversion of Stock, Shares Converted |  |  | 13,672,173 |  |  |  |  |  |  |  |  |  |  |  |
Exercise price per warrant |  |  |  |  |  |  |  |  | $ 0.69 |  |  |  |  |  |
Percentage of issue of the public offering |  |  |  |  |  |  |  |  | 120.00% |  |  |  |  |  |
Preferred Stock Redemption Discount |  | $ 900,000 |  |  |  |  |  | $ 1,400,000 |  | 1,500,000 | 1,400,000 |  |  |  |
Preferred stock accrued dividends |  |  |  |  |  |  |  |  |  | $ 1,496,000 | 1,380,000 |  |  |  |
Preferred Stock Redemption Discount |  |  |  |  |  |  |  |  |  |  | $ 1,400,000 |  |  |  |
Investment Warrants Expiration Date1 |  |  |  |  |  |  |  |  | Oct. 15, 2023 |  |  |  |  |  |
Series B Preferred Stock [Member] | Over-Allotment Option [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues |  |  |  | 2,428,825 |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right, Number of Securities Called by Warrants or Rights |  |  |  | 2,428,825 |  |  |  |  |  |  |  |  |  |  |
Issue of warrants to purchase common stock |  |  |  | 1,807,826 |  |  |  |  |  |  |  |  |  |  |
Common Class A [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues |  |  | 2,520,000 |  |  |  |  |  |  |  |  |  |  |  |
Shares Issued, Price Per Share |  |  | $ 1.15 |  |  |  |  |  |  |  |  |  |  |  |
Common Class B [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues |  |  | 15,723 |  |  |  |  |  |  |  |  |  |  |  |

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