XML 53 R41.htm IDEA: XBRL DOCUMENT
v3.19.1

Stockholders' Equity (Details Textual) - USD ($) |  |  |  |  |  |  |  | 1 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 01, 2019 | Mar. 13, 2018 | Mar. 12, 2018 | Aug. 03, 2017 | Apr. 07, 2017 | Mar. 13, 2017 | Mar. 13, 2016 | Jan. 31, 2019 | Jun. 30, 2018 | Aug. 31, 2017 | Apr. 24, 2017 | Mar. 31, 2017 | Feb. 28, 2017 | Jan. 31, 2017 | Oct. 31, 2016 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Jul. 31, 2018 | Dec. 12, 2016 | Jul. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 26,610,183 | 25,236,255 |  |  |  |
Common Stock, Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50,000,000 | 50,000,000 |  |  |  |
Common Stock, Par or Stated Value Per Share |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.0001 | $ 0.0001 |  |  |  |
Common Stock, Voting Rights |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.1 |  |  |  |  |
Warrants Issued |  |  |  |  |  |  |  |  |  |  |  | 16,000 |  | 2,134,193 |  |  |  |  |  |  |
Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 34,000 | $ 10,000 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,500,000 |  |  |  |  |
Common Stock, Shares Subscribed but Unissued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 709,314 | 834,756 |  |  |  |
Common Stock, Value, Subscriptions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,085,000 | $ 9,558,000 |  |  |  |
Shares Issued, Price Per Share |  |  | $ 11.45 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments of Stock Issuance Costs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 5,674,000 |  |  |  |
Preferred Stock, Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,000,000 | 2,000,000 |  |  |  |
Stock Issued During Period, Value, Issued for Services |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,700,000 |  |  |  |  |  |  |  |
Proceeds from Issuance of Private Placement |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 10,000,000 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | The remaining 50% (the “Performance Options”) vest and become exercisable upon the occurrence of the following milestones being achieved: (i) 25% of the Performance Options vest upon the dosing of the first patient in the first Phase 2 clinical trial of any Company product candidate, (ii) 25% of the Performance Options vest upon the dosing of the first patient in the first Phase 2 clinical trial of a second Company product candidate, (iii) 25% of the Performance Options vest upon the Company’s achievement of a fully-diluted market capitalization of $500,000,000 and (iv) 25% of the Performance Options vest upon the Company’s achievement of a fully-diluted market capitalization of $1,000,000,000. |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5.73 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.00% |  |  |  |  |
Research and Development Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,100,000 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,049,689 |  |  |  |  |
Maximum Value Of Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 75,000,000 |  |
Commission Rate Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.00% |  |
Preferred Stock, Dividend Rate, Percentage |  |  |  |  |  |  |  | 2.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized |  |  |  |  |  |  |  |  | 5,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized |  |  |  |  |  |  |  |  | 3,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Incentive Plan 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,000,000 |  |  |  |  |
Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 years 6 months |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5.78 | $ 5.73 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 68,158 |  |  |  |  |
Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,200,000 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,072,000 | 134,000 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 years 2 months 12 days |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 8.16 | $ 6.53 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 230,000 |  |  |  |  |
Employee Stock Option [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchased During Period, Shares |  |  |  |  |  |  |  |  |  |  | 1,041,675 |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,100,000 |  |  |  |  |
Shares Issued, Price Per Share |  |  |  |  | $ 5.73 |  |  |  |  |  | $ 5.73 |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Issued for Services |  |  |  |  | 200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 years |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeiture Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.00% |  |  |  |
Employee Stock Option [Member] | Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5.73 |  |  |  |  |
General and Administrative Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,200,000 |  |  |  |  |
Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred Stock, Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,000,000 | 2,000,000 |  |  |  |
Unregistered Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues |  |  |  |  |  |  |  |  |  |  |  | 64,000 |  | 8,536,774 |  |  |  |  |  |  |
Common Class B [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15,000,000
Common Class A [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 | 1,000,000 |  |  |  |
Common Stock, Shares Authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 |  |  |
Fortress Biotech, Inc [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued |  |  | 834,756 |  |  |  |  |  |  | 365,639 |  |  |  |  |  |  |  |  |  |  |
Common Stock, Value, Subscriptions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 900,000 |
Shares Issued, Price Per Share |  |  |  |  |  | $ 5.73 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Issued for Services | 709,314 |  |  |  |  | 767,264 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Value, Issued for Services |  |  |  |  |  | $ 4,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and Development Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 9,600,000 |  |  |  |
Common Stock, Capital Shares Reserved for Future Issuance |  | 834,756 | 834,756 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred Stock, Dividend Rate, Percentage | 2.00% | 2.50% | 2.50% |  |  |  |  |  |  | 2.50% |  |  |  |  |  |  |  |  |  |  |
Fortress Biotech, Inc [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares Of Common Stock, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.50% |  |  |  |  |
Stock Issued During Period, Shares, New Issues |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 982,533 |  |  |  |  |
Common Stock, Shares Subscribed but Unissued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,000,000 |  |  |
Research and Development Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 9,600,000 |  |  |  |
Fortress Biotech, Inc [Member] | Common Class B [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued |  |  |  |  |  |  | 250,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares Subscribed but Unissued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,000,000 |  |  |
Diluted Outstanding Equity, Percentage |  |  |  |  |  |  | 2.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fortress Biotech, Inc [Member] | Common Stock B Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued |  |  |  |  |  | 767,264 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Research and Development Expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,400,000 |  |  |
Preferred Stock, Dividend Rate, Percentage |  |  |  |  |  | 2.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
National Holdings Corporation [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrants Issued |  |  |  | 2,500 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
National Holdings Corporation [Member] | Unregistered Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues |  |  |  | 10,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
City of Hope National Medical Center [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues |  |  |  |  |  |  |  |  |  |  |  |  | 293,588 |  |  |  |  |  |  |  |
City of Hope National Medical Center [Member] | Common Stock [Member] | Original Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares, Issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 293,588 |  |  |  |  |
City of Hope National Medical Center [Member] | Common Class A [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares, Issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 |  |  |  |  |
National Securities, Inc [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage Of Shares Issued To Placement Agent |  |  |  | 10.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrants Issued |  |  |  | 1,000 |  |  |  |  |  |  |  | 6,400 |  | 853,677 |  |  |  |  |  |  |
Private Placement [Member] | National Holdings Corporation [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage Of Placement Agent Fee |  |  |  |  |  |  |  |  |  |  |  | 10.00% |  | 10.00% |  |  |  |  |  |  |
Percentage Of Shares Issued To Placement Agent |  |  |  |  |  |  |  |  |  |  |  | 10.00% |  | 10.00% |  |  |  |  |  |  |
Payments of Stock Issuance Costs |  |  |  |  |  |  |  |  |  |  |  | $ 42,000 |  | $ 5,500,000 |  |  |  |  |  |  |
Proceeds from Issuance of Private Placement |  |  |  | $ 65,000 |  |  |  |  |  |  |  | $ 400,000 |  | $ 55,500,000 |  |  |  |  |  |  |

X
- Definition Percentage of commission rate on gross sale of common stock. + References No definition available. + Details
Name: | mbio_CommissionRatePercentage
Namespace Prefix: | mbio_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Represents the percentage of diluted outstanding equity. + References No definition available. + Details
Name: | mbio_DilutedOutstandingEquityPercentage
Namespace Prefix: | mbio_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the maximum amount of shares authorized to sell. + References No definition available. + Details
Name: | mbio_MaximumValueOfSharesAuthorized
Namespace Prefix: | mbio_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition It represents the percentage of placement agent fee. + References No definition available. + Details
Name: | mbio_PercentageOfPlacementAgentFee
Namespace Prefix: | mbio_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The percentage of shares issued to the placement agent. + References No definition available. + Details
Name: | mbio_PercentageOfSharesIssuedToPlacementAgent
Namespace Prefix: | mbio_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The estimated forfeiture rate for share based payment awards. + References No definition available. + Details
Name: | mbio_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsForfeitureRate
Namespace Prefix: | mbio_
Data Type: | num:percentItemType
Balance Type: | na
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