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v3.23.1

Stockholders' Equity (Details) |  |  |  |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |  |  |  |  |  |  |  |  |
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Dec. 22, 2022 USD ($) $ / shares shares | Aug. 03, 2022 $ / shares | Jul. 29, 2022 USD ($) $ / shares shares | Jul. 28, 2022 Vote | Jan. 27, 2021 $ / shares | Nov. 16, 2020 USD ($) $ / shares shares | Oct. 15, 2018 USD ($) $ / shares shares | Oct. 10, 2018 shares | Oct. 10, 2018 shares | Sep. 11, 2017 USD ($) $ / shares shares | Feb. 28, 2021 shares | Jan. 31, 2021 shares | Sep. 30, 2022 USD ($) $ / shares shares | Mar. 31, 2022 shares | Sep. 30, 2022 USD ($) $ / shares shares | Dec. 31, 2022 USD ($) $ / shares shares | Dec. 31, 2021 USD ($) $ / shares shares | Dec. 31, 2020 USD ($) | Dec. 31, 2017 USD ($) | Oct. 26, 2022 shares | Jul. 25, 2022 shares | Jul. 24, 2022 shares | Jul. 11, 2022 $ / shares | Jun. 30, 2022 $ / shares shares | Sep. 30, 2021 $ / shares | Jul. 29, 2021 $ / shares shares | Mar. 31, 2021 shares | Mar. 29, 2021 | Aug. 05, 2016
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Offering price | $ / shares |  |  | $ 8.00 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds | $ |  |  | $ 3,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Conversion price | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1.22 |  |  |
Common stock, shares issued |  |  |  |  |  |  | 252,000 |  |  |  |  |  | 15,844,294 |  | 15,844,294 | 15,844,294 | 13,204,487 |  |  |  |  |  |  | 15,844,294 |  | 2,459,016 |  |  |
Common stock, par value (in dollars per share) | $ / shares |  | $ 0.001 |  |  |  |  | $ 1,000 |  |  |  |  |  | $ 0.001 |  | $ 0.001 | $ 0.001 | $ 0.001 |  |  |  |  |  | $ 0.001 | $ 0.001 |  | $ 0.001 |  |  |
Common stock, shares authorized |  |  |  |  |  |  |  |  |  |  |  |  | 20,000,000 |  | 20,000,000 | 20,000,000 | 20,000,000 |  |  | 350,000,000 | 20,000,000 | 200,000,000 |  | 20,000,000 |  |  |  |  |
Votes relating to preferred stock | Vote |  |  |  | 1,549,295 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance or sale of equity | $ |  |  |  |  |  |  | $ 18,600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant term |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price per share | $ / shares |  | 6.90 |  |  |  | $ 13.80 | $ 13.80 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Price per share | $ / shares |  |  |  |  |  |  | 1.22 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Over allotment option period |  |  |  |  |  |  |  | 45 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock of convertible conversion price decrease | $ / shares |  | 1.22 |  |  | $ 15.0 | 6.90 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deemed dividend | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 340,000 |  | $ 340,000 | $ 340,000 | $ 0 |  |  |  |  |  |  |  |  |  |  |  |
Stock issued for exercise of stock options (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock shares converted |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 398 |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, par or stated value per share | $ / shares |  |  |  |  |  | $ 0.001 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock issued upon conversion |  |  |  |  |  |  |  |  |  |  | 899,677 | 899,677 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated fair value of inducement consideration | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 7,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | $ 65,960,000 |  |  |  |  |  |  |  |  |  |  |  |
Effect of Warrant exercise price adjustment | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 340,000 | 340,000 | 0 | $ 900,000 |  |  |  |  |  |  |  |  |  |  |
Stock Purchase Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consideration received on transaction | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,900,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 66,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Share Repurchase Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Price per share | $ / shares | $ 0.4001 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate purchase price | $ | $ 288,072 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Over-allotment option |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued |  |  |  |  |  | 242,883 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants to purchase shares |  |  |  |  |  | 242,883 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issue of warrants to purchase common stock |  |  |  |  |  | 180,783 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
FBR Capital Markets Co |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Brokerage commission percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.00%
Warrant |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price per share | $ / shares |  |  |  |  |  | $ 6.90 | $ 6.90 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants to purchase shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,165,575 |  |
Three founders of subsidiary | Share Repurchase Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, par value (in dollars per share) | $ / shares | $ 0.001 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares repurchased | 720,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Series A Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Conversion price | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 189 |  |  |  |
Preferred stock conversion price per share | $ / shares |  |  |  |  |  |  |  |  |  | $ 5.40 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock of convertible conversion price decrease | $ / shares |  |  |  |  | $ 15 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock shares converted |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock redemption discount | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 100,000 |  |  | $ 6,900,000 |  |  |  |  |  |  |  |  |  |
Preferred stock, dividend rate percentage |  |  |  |  |  |  |  |  |  | 2.00% |  |  |  |  |  |  |  |  | 2.00% |  |  |  |  |  |  |  |  |  |
Preferred stock of convertible conversion price increase | $ / shares |  |  |  |  |  |  |  |  |  | $ 189.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum percentage |  |  |  |  | 4.99% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9.99% |
Number of common shares issued for convertible preferred stock |  |  |  |  |  |  |  |  |  |  |  |  |  | 900,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock accrued dividends | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 24,000 | $ 254,000 |  |  |  |  |  |  |  |  |  |  |
Preferred stock, redemption terms |  |  |  |  |  |  |  |  |  | (i) the VWAP (as defined in the Certificate of Designation) for at least20 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 | Private Placement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued |  |  |  |  |  |  |  |  |  | 12,000 | 12,000 | 12,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Price per share | $ / shares |  |  |  |  |  |  |  |  |  | $ 10 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, par or stated value per share | $ / shares |  |  |  |  |  |  |  |  |  | $ 0.001 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of convertible preferred stock | $ |  |  |  |  |  |  |  |  |  | $ 12,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Series B Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period value, issued for services | $ |  |  |  |  |  |  | $ 1,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock conversion price per share | $ / shares |  |  |  |  |  |  | $ 11.50 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deemed dividend | $ |  |  |  |  |  | $ 880,000,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued for exercise of stock options (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock redemption discount | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock accrued dividends | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,496,000 |  |  |  |  |  |  |  |  |  |  |  |
Series B Preferred Stock | Over-allotment option |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued |  |  |  |  |  |  |  |  | 242,883 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants to purchase shares |  |  |  |  |  |  |  | 242,883 | 242,883 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issue of warrants to purchase common stock |  |  |  |  |  |  |  | 180,783 | 180,783 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Series B Preferred Stock | Warrant |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants to purchase shares |  |  |  |  |  |  | 1,367,218 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Series C convertible preferred stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock, shares issued |  |  | 275,000 |  |  |  |  |  |  |  |  |  | 275,000 |  | 275,000 | 275,000 | 275,000 |  |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock, par value (in dollars per share) | $ / shares |  |  | $ 0.001 |  |  |  |  |  |  |  |  |  | $ 0.001 |  | $ 0.001 | $ 0.001 | $ 0.001 |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,006,000 | $ 2,006,000 | $ 0 |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock of convertible conversion price decrease | $ / shares |  | $ 1.22 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Series D convertible preferred stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock, shares issued |  |  | 100,000 |  |  |  |  |  |  |  |  |  | 100,000 |  | 100,000 | 100,000 | 100,000 |  |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock, par value (in dollars per share) | $ / shares |  |  | $ 0.001 |  |  |  |  |  |  |  |  |  | $ 0.001 |  | $ 0.001 | $ 0.001 | $ 0.001 |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 728,000 | $ 728,000 | $ 0 |  |  |  |  |  |  |  |  |  |  |  |
Votes per share |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Class A common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued |  |  |  |  |  |  | 252,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant term |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price per share | $ / shares |  |  |  |  |  |  | $ 13.80 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants to purchase shares |  |  |  |  |  |  | 252,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class B common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stockholder's Equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued |  |  |  |  |  |  | 15,723 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Percentage of beneficial ownership. + References No definition available. + Details
Name: | syn_BeneficialOwnershipPercentage
Namespace Prefix: | syn_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

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- Definition Represent that percentage of commission revenue from buying and selling securities on behalf of customers. + References No definition available. + Details
Name: | syn_BrokerageCommissionPercentage
Namespace Prefix: | syn_
Data Type: | dtr-types:percentItemType
Balance Type: | na
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