Fortress Biotech, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Debt and Interest (Narrative) (Details)

Debt and Interest (Narrative) (Details) - USD ($)				1 Months Ended		3 Months Ended			9 Months Ended
Debt and Interest (Narrative) (Details) - USD ($)	Nov. 14, 2023	Apr. 11, 2023	Dec. 30, 2022	Jul. 31, 2023	Feb. 28, 2023	Sep. 30, 2023	Feb. 28, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Jun. 13, 2023	Dec. 31, 2022	Aug. 31, 2020	Aug. 29, 2020
Debt Instrument [Line Items]
Sale of stock, net proceeds	$ 8,900,000		$ 150,000,000	$ 9,100,000	$ 6,700,000
Total notes payable						$ 45,791,000			$ 45,791,000			$ 91,730,000
Unamortized debt discount fees						4,209,000			4,209,000			$ 9,320,000
Debt instrument, interest expense						1,877,000		$ 2,839,000	10,400,000	$ 7,397,000
Repayments of debt									50,375,000	0
Number of shares called by warrants					1		1
Exercise price of warrants											$ 8.136
Fair Value Adjustment of Warrants						(4,542,000)			(10,708,000)
Amortization of debt discount									2,524,000	1,500,000
Stock offering, number of shares issued			4,900,000		1,180,000
Stock offering, price per share					$ 5.25		$ 5.25
Loss on extinguishment of debt									(2,796,000)	0
Oaktree Note [Member]
Debt Instrument [Line Items]
Debt instrument face amount													$ 60,000,000.0
Debt instrument, interest expense						$ 1,425,000		1,406,000	$ 4,206,000	4,171,000
Debt instrument, stated interest rate						11.00%			11.00%
Exercise price of warrants														$ 48.00
Oaktree Note [Member] \| Minimum
Debt Instrument [Line Items]
Warrants issued														100,000
EWB Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument, stated interest rate						10.20%			10.20%
Runway Note [Member]
Debt Instrument [Line Items]
Debt instrument, stated interest rate						13.77%			13.77%
Loss on extinguishment of debt		$ (2,800,000)
Partner Company Promissory Note
Debt Instrument [Line Items]
Debt instrument, interest expense						$ 33,000		$ 1,221,000	$ 4,834,000	$ 2,570,000
Interest Expense
Debt Instrument [Line Items]
Fair Value Adjustment of Warrants									300,000
Journey \| EWB Term Loan [Member] \| East West Bank ("EWB Loan") [Member]
Debt Instrument [Line Items]
Amount outstanding				0
Repayments of debt				$ 10,000,000.0
Mustang \| Runway Note [Member]
Debt Instrument [Line Items]
Term Loan payoff amount		$ 30,700,000
Mustang \| Interest Expense \| Runway Note [Member]
Debt Instrument [Line Items]
Loss on extinguishment of debt									(2,800,000)
Urica \| Placement Agent Warrants [Member]
Debt Instrument [Line Items]
Fair Value Adjustment of Warrants									16,000
Urica \| 8% Cumulative Convertible Class B Preferred Offering
Debt Instrument [Line Items]
Warrants, fair value					$ 100,000		$ 100,000
Common stock's average 10-day trading price discount percentage							7.50%
Interest expense						$ 100,000			$ 200,000
Stock offering, number of shares issued							135,494
Stock offering, gross proceeds							$ 3,400,000
Stock offering, aggregate fees paid							$ 500,000
Stock offering, price per share					$ 25.00		$ 25.00
Preferred Stock, dividend rate percentage							8.00%
Aggregate gross proceeds from convertible preferred stock					$ 20,000,000		$ 20,000,000
Percentage of discounted price							20.00%