Mustang Bio, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document And Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Related Party Agreements (Details Textual)

v3.10.0.1

Related Party Agreements (Details Textual) - USD ($)		1 Months Ended		3 Months Ended		9 Months Ended		12 Months Ended
Related Party Agreements (Details Textual) - USD ($)	Feb. 02, 2018	Jul. 31, 2016	Mar. 31, 2015	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Common Stock, Shares, Outstanding				26,263,631		26,263,631		25,236,255
Annual Fees Expenses On Founders Agreement				$ 100,000	$ 100,000	$ 400,000	$ 400,000
Fortress Biotech, Inc [Member]
Annual Consulting Fees			$ 500,000
Increase In Annual Consulting Fees			1,000,000
Excess In Net Assets Value			$ 100,000,000
Research and Development Asset Acquired Other than Through Business Combination, Fair Value Acquired								$ 9,600,000	$ 4,400,000
Fortress Biotech, Inc [Member] \| Research and Development Expense [Member]
Annual Fees Expenses On Founders Agreement Percentage				50.00%	50.00%	50.00%	50.00%
Fortress Biotech, Inc [Member] \| General and Administrative Expense [Member]
Annual Fees Expenses On Founders Agreement Percentage				50.00%	50.00%	50.00%	50.00%
National Holdings, Inc. [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures					$ 5,600,000		$ 5,600,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights					861,077		861,077
City Of Hope [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners				4.70%		4.70%
TG Therapeutics, Inc. [Member]
Revenues	$ 50,000
Series A Preferred Stock [Member]
Stock Issued During Period, Shares, Issued for Services						0
Series A Preferred Stock [Member] \| Fortress Biotech, Inc [Member]
Stock Issued During Period, Shares, Issued for Services		250,000
Preferred Stock, Dividend Rate, Percentage		2.50%
Common Stock A One [Member] \| City Of Hope [Member]
Common Stock, Shares, Outstanding				1,000,000		1,000,000
Common Stock A Two [Member] \| City Of Hope [Member]
Common Stock, Shares, Outstanding				293,588		293,588

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