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

Related Party Transactions (PIK Dividend or Equity Fee Payable) (Details)	3 Months Ended
	Mar. 31, 2024
Avenue
Related Party Transaction [Line Items]
Effective date	Feb. 17, 2015
PIK dividend as a percentage of fully diluted outstanding capitalization	2.50%
Baergic
Related Party Transaction [Line Items]
Effective date	Dec. 17, 2019
Cellvation
Related Party Transaction [Line Items]
Effective date	Oct. 31, 2016
PIK dividend as a percentage of fully diluted outstanding capitalization	2.50%
Checkpoint
Related Party Transaction [Line Items]
Effective date	Mar. 17, 2015
Annual equity fee as a percentage of fully diluted outstanding capitalization	2.50%
Cyprium
Related Party Transaction [Line Items]
Effective date	Mar. 13, 2017
PIK dividend as a percentage of fully diluted outstanding capitalization	2.50%
Helocyte
Related Party Transaction [Line Items]
Effective date	Mar. 20, 2015
PIK dividend as a percentage of fully diluted outstanding capitalization	2.50%
Mustang
Related Party Transaction [Line Items]
Effective date	Mar. 13, 2015
PIK dividend as a percentage of fully diluted outstanding capitalization	2.50%
Oncogenuity
Related Party Transaction [Line Items]
Effective date	Apr. 22, 2020
PIK dividend as a percentage of fully diluted outstanding capitalization	2.50%
Urica
Related Party Transaction [Line Items]
Effective date	Nov. 07, 2017
PIK dividend as a percentage of fully diluted outstanding capitalization	2.50%