Fortress Biotech, Inc. Annual report pursuant to Section 13 and 15(d)

Annual report pursuant to Section 13 and 15(d)

Sponsored Research and Clinical Trial Agreements - Additional Information (Details)

Sponsored Research and Clinical Trial Agreements - Additional Information (Details) - USD ($)									1 Months Ended			12 Months Ended
	Mar. 12, 2018	Mar. 12, 2018	Jan. 03, 2018	Nov. 30, 2017	Nov. 28, 2017	Jul. 03, 2017	Feb. 17, 2017	Mar. 31, 2015	Dec. 31, 2019	Jun. 30, 2017	Feb. 17, 2017	Dec. 31, 2019	Dec. 31, 2018	Oct. 31, 2016
Research and Development Expense												$ 81,326,000	$ 87,383,000
Sponsor Research Agreement Funding Commitment			$ 900,000	$ 2,300,000
Research and Development Expense (Excluding Acquired in Process Cost)												75,236,000	83,333,000
Research and Development Arrangement, Contract to Perform for Others, Costs Incurred, Gross	$ 100,000
Payment of Upfront Fees												1,000,000
Revenue Recognition Milestone Method Payments Due												14,500,000
Research and Development Arrangement, Contract to Perform for Others, Description and Terms			2 years
Umass Sponsored Research Agreement [Member]
Research and Development Expense												800,000
Payments For Research And Development Expenses												800,000
Sponsor Research Agreement Funding Commitment									$ 0			0	800,000
UPenn Sponsored Research Agreement [Member]
Research and Development Expense												2,000,000
Payments For Research And Development Expenses												300,000
Sponsor Research Agreement Funding Commitment									1,100,000			1,100,000	500,000
Sponsored Research Agreement [Member]
Research and Development Expense (Excluding Acquired in Process Cost)												100,000	0
Checkpoint [Member]
Reimbursement Of Cost Recognized As Revenue												0	35,000
AR CD123 License [Member]
Revenue Recognition Milestone Method Payments Due Over Three Years							$ 200,000
Caelum [Member]
Payments For Research And Development Expenses												100,000
Research and Development Arrangement, Contract to Perform for Others, Costs Incurred, Gross		$ 100,000
Cellvation [Member]
Research and Development Expense													300,000
Payments For Research And Development Expenses												100,000
Research And Development Expense Payable Milestone Payment														$ 800,000
Helocyte Inc [Member]
Payments For Research And Development Expenses												0	100,000
Payment of Upfront										$ 1,500,000
Pentamer [Member]
Payments For Research And Development Expenses												0	1,300,000
City of Hope (COH) [Member]
Research and Development Expense												500,000	500,000
City of Hope (COH) [Member] \| AR CD123 License [Member]
Research and Development Expense												1,200,000	800,000
Payment of Upfront Fees							20,000
Revenue Recognition Milestone Method Payments Due							100,000
Mustang [Member]
Research and Development Expense												2,000,000	2,000,000
Mustang [Member] \| COH [Member]
Amount payable for research								$ 2,000,000
Mustang Bio, Inc [Member]
Research and Development Expense												800,000	1,300,000
Research And Development Expense Payable Milestone Payment							200,000				$ 200,000
Payment of Upfront Fees							$ 9,300
Revenue Recognition Milestone Method Payments Due											$ 100,000
Mustang Bio, Inc [Member] \| AR IL-13 License [Member]
Research and Development Expense												900,000	1,100,000
Mustang Bio, Inc [Member] \| CD20 Technology License [Member]
Payment of Upfront Fees						$ 5,300,000
Mustang Bio, Inc [Member] \| Beth Israel Deaconess Medical Center - CRISPR (multiple programs)[Member]
Research and Development Expense												100,000	100,000
Payment of Upfront Fees					$ 800,000
Mustang Bio, Inc [Member] \| S Agreement with St. Jude
Research and Development Expense												800,000
Payment of Upfront Fees									$ 800,000
Tamid [Member]
Research and Development Expense												$ 0	$ 700,000
Research and development payments due				$ 800,000