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Related Party Agreements (Details Textual) - USD ($) | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jan. 31, 2017 | Jul. 26, 2016 | May 17, 2016 | Dec. 31, 2018 | Dec. 31, 2017 | Nov. 14, 2018 | Dec. 31, 2016
Founders Agreement Term |  |  | 15 years |  |  |  |
Additional Consideration Under Founders Agreement Description |  |  | (i) pay an equity fee in shares of common stock, payable within five (5) business days of the closing of any equity or debt financing for Mustang that occurs after the effective date of the Mustang Founders Agreement and ending on the date when Fortress no longer has majority voting control in the Company’s voting equity, equal to two and one-half (2.5%) of the gross amount of any such equity or debt financing; and (ii) pay a cash fee equal to four and one-half percent (4.5%) of the Company’s annual net sales, payable on an annual basis, within ninety (90) days of the end of each calendar year. In the event of a Change in Control, the Company will pay a one-time change in control fee equal to five (5x) times the product of (A) net sales for the twelve (12) months immediately preceding the change in control and (B) four and one-half percent (4.5%) (see Note 7). |  |  |  |
Annual Fees Expenses On Founders Agreement |  |  |  | $ 500,000 | $ 500,000 |  |
Business Acquisition, Percentage of Voting Interests Acquired |  |  |  | 32.10% |  |  |
Class of Warrant or Right, Number of Securities Called by Warrants or Rights |  |  |  |  |  |  | 601,486
Allocated Share-based Compensation Expense |  |  |  | $ 34,000 | 10,000 |  |
Salary and Wage, Officer, Excluding Cost of Good and Service Sold |  |  |  | 84,000 | 25,052 |  |
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures |  |  |  | $ 4,960,000 | $ 2,012,000 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross |  |  |  | 5,500,000 |  |  |
Restricted Stock [Member] |  |  |  |  |  |  |
Allocated Share-based Compensation Expense |  |  |  | $ 1,900,000 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross |  |  |  | 322,636 | 180,000 |  |
Private Placement [Member] |  |  |  |  |  |  |
Class of Warrant or Right, Exercise Price of Warrants or Rights |  |  |  |  | $ 8.50 |  | $ 8.50
Director [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Description |  |  |  | Dr. Rosenwald will receive a cash fee of $50,000 per year paid quarterly and an annual stock award of the greater of (i) a number of shares of common stock having a fair market value on the grant date of $50,000 or (ii) 10,000 shares of common stock, which shares shall vest and become non-forfeitable on the third anniversary of the grant date, subject to continued service on the Board on such date. |  |  |
Board of Directors Chairman [Member] |  |  |  |  |  |  |
Professional Fees |  |  |  | $ 84,000 | $ 70,800 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Description |  |  |  | 20,000 |  |  |
Allocated Share-based Compensation Expense |  |  |  | $ 34,000 | $ 10,800 |  |
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures | $ 50,000 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | 10,000 |  |  |  | 10,000 |  |
Board of Directors Chairman [Member] | Restricted Stock [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  | 20,000 | 10,000 |  |
Fortress Biotech, Inc [Member] |  |  |  |  |  |  |
Proceeds from Related Party Debt |  | $ 2,000,000 |  |  |  |  |
Annual Consulting Fees |  |  |  | $ 500,000 |  |  |
Increase In Annual Consulting Fees |  |  |  | 1,000,000 |  |  |
Excess In Net Assets Value |  |  |  | 100,000,000 |  |  |
National Holdings, Inc. [Member] |  |  |  |  |  |  |
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures |  |  |  |  | $ 5,600,000 |  | $ 4,000,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights |  |  |  |  | 861,077 |  |
Sale of Stock, Price Per Share |  |  |  |  |  | $ 3.25 |
Advisor [Member] |  |  |  |  |  |  |
Annual Consulting Fees |  |  |  | 60,000 |  |  |
Common Class B [Member] |  |  |  |  |  |  |
Conversion of Stock, Shares Converted |  | 7,250,000 |  |  |  |  |
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures |  |  |  | 0 | $ 0 |  |
Series A Preferred Stock [Member] |  |  |  |  |  |  |
Preferred Stock, Voting Rights |  |  | Each share of Class A Preferred Stock is convertible, at Fortress’ option, into one fully paid and nonassessable share of Mustang common stock, subject to certain adjustments. As holders of Class A Preferred Stock, Fortress will receive on each March 13 (each a “PIK Dividend Payment Date”) until the date all outstanding Class A Preferred Stock is converted into common stock or redeemed (and the purchase price is paid in full), pro rata per share dividends paid in additional fully paid and nonassessable shares of common stock (“PIK Dividends”) such that the aggregate number of shares of common stock issued pursuant to such PIK Dividend is equal to two and one-half percent (2.5%) of Mustang’s fully-diluted outstanding capitalization on the date that is one (1) business day prior to any PIK Dividend Payment Date. |  |  |  |
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures |  |  |  | $ 0 | $ 0 |  |
Convertible Common Stock [Member] |  |  |  |  |  |  |
Conversion of Stock, Shares Issued |  | 7,000,000 |  |  |  |  |
Common Stock A One [Member] |  |  |  |  |  |  |
Conversion of Stock, Shares Converted |  | 250,000 |  |  |  |  |

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