XML 43 R34.htm IDEA: XBRL DOCUMENT
v3.20.1

License, Clinical Trial and Sponsored Research Agreements - Sponsored (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |
Research and development | $ 30,042 | $ 21,104
City Of Hope National Medical Center ("COH") [Member] | Sponsored Research And Clinical Trial Agreements [Member] |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |
Research and development | 6,143 | 5,719
City of Hope [Member] | City Of Hope National Medical Center ("COH") [Member] | Sponsored Research And Clinical Trial Agreements [Member] |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |
Research and development | 2,000 | 2,000
CD123 Product Or Process [Member] | City Of Hope National Medical Center ("COH") [Member] | Sponsored Research And Clinical Trial Agreements [Member] |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |
Research and development | 1,202 | 835
Il13r2 Product [Member] | City Of Hope National Medical Center ("COH") [Member] | Sponsored Research And Clinical Trial Agreements [Member] |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |
Research and development | 876 | 1,056
Manufacturing | City Of Hope National Medical Center ("COH") [Member] | Sponsored Research And Clinical Trial Agreements [Member] |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |
Research and development | 457 | 458
Fred Hutch CD 20 [Member] | City Of Hope National Medical Center ("COH") [Member] | Sponsored Research And Clinical Trial Agreements [Member] |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |
Research and development | 762 | 1,301
ST Jude XSCID [Member] | City Of Hope National Medical Center ("COH") [Member] | Sponsored Research And Clinical Trial Agreements [Member] |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |
Research and development | 777 |
Crispr [Member] | City Of Hope National Medical Center ("COH") [Member] | Sponsored Research And Clinical Trial Agreements [Member] |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |
Research and development | $ 69 | $ 69

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The costs incurred in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, excluding in-process research and development acquired in a business combination consummated during the period. Excludes software research and development, which has a separate concept. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 730 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373 + Details
Name: | us-gaap_ResearchAndDevelopmentExpenseExcludingAcquiredInProcessCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | srt_CounterpartyNameAxis=mbio_CityOfHopeNationalMedicalCenterCohMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=mbio_SponsoredResearchAndClinicalTrialAgreementsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=mbio_CityOfHopeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=mbio_Cd123ProductOrProcessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=mbio_Il13r2ProductMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=us-gaap_LicenseAndMaintenanceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=mbio_FredHutchCd20Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=mbio_StJudeXscidMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=mbio_CrisprMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |