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

Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity (Capital Raises) (Narrative) (Details)

Stockholders' Equity (Capital Raises) (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands							1 Months Ended				3 Months Ended		6 Months Ended
	Jun. 27, 2024	Jun. 12, 2024	Jan. 05, 2024	May 05, 2023	Dec. 30, 2022	Apr. 23, 2021	Jun. 30, 2024	May 31, 2024	Apr. 30, 2024	Jan. 31, 2024	Jun. 30, 2023	Feb. 28, 2023	Jun. 30, 2024	Jun. 30, 2023	May 17, 2024	Jan. 09, 2024	Dec. 31, 2023	Oct. 11, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, number of shares issued					4,900,000
Common Stock, par value					$ 0.0001		$ 0.001						$ 0.001				$ 0.001
Warrants exercised, Number of shares													17,500
Sale of stock, net proceeds					$ 150,000
Proceeds from Issuance of Common Stock													$ 2,826	$ 1,168
Gain (loss) on common stock warrant liabilities											$ 512			(6,166)
Aggregate purchase price											$ (41)		10,118	13,154
Exercise of warrants for cash													$ 30	$ 0
Avenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants to purchase shares									689,680
Exercise price of warrants									$ 6.20									$ 116.25
Avenue \| Series A Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, price per share																$ 22.545
Avenue \| Series B Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, price per share																$ 22.545
Avenue \| Unregistered warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants to purchase shares									1,379,360
Stock offering, price per share									$ 0.125
Exercise price of warrants									$ 6.20
Net proceeds								$ 3,900	$ 3,700
Urica \| Common Stock Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of warrants	$ 1.68
Warrant expiration term	5 years
Urica \| Convertible Class B Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, number of shares issued												135,494
Stock offering, price per share												$ 25.00
Stock offering, gross proceeds												$ 3,400
Stock offering, aggregate fees paid												$ 500
Preferred Stock, dividend rate percentage	8.00%											8.00%
Maximum \| Avenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant expiration term									5 years
Minimum \| Avenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant expiration term									18 months
At the Market Offering [Member] \| MLV & Co. and FBR Capital Markets & Co [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, number of shares issued													1,600,000	0.1
At the Market Offering [Member] \| Cantor Fitzgerald & Co., Oppenheimer & Co., Inc., H.C. Wainwright & Co. Inc., Jones Trading Institutional Services LLC. B. Riley and Dawson James Securities, Inc [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, price per share							1.87				$ 11.31		$ 1.87	$ 11.31
Stock offering, gross proceeds													$ 2,900	$ 1,200
At the Market Offering [Member] \| Journey
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, number of shares issued													300,000
Stock offering, price per share							$ 5.28						$ 5.28
Number of Shares issuable for At-the-Market offering													3,861,553
Stock offering, gross proceeds													$ 1,500
At the Market Offering [Member] \| Checkpoint \| Founders Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, number of shares issued													193,905
Shares issued (in percent)													2.50%
At the Market Offering [Member] \| Mustang \| Founders Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, number of shares issued													0	0
At the Market Offering [Member] \| Avenue \| Founders Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, number of shares issued													25,567
At the Market Offering [Member] \| Avenue \| Unregistered warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants to purchase shares							87,683						87,683
Net proceeds													$ 300
Public Offering [Member] \| Mustang
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, number of shares issued								1,160,000
Number of warrants to purchase shares								50,632,914
Stock offering, price per share								$ 0.237
Exercise price of warrants								$ 0.237
Warrants exercised, Number of shares								15,717,638
Exercise of warrants for cash								$ 3,300
Public Offering [Member] \| Mustang \| Series A One Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant expiration term								5 years
Public Offering [Member] \| Mustang \| Series A Two Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant expiration term								24 months
Public Offering [Member] \| Mustang \| Series A Three Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant expiration term								9 months
Public Offering [Member] \| Mustang \| Amended Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants to purchase shares								2,588,236
Stock offering, price per share								$ 1.58
Exercise price of warrants								$ 0.237
Warrant expiration term								5 years
Public Offering [Member] \| Mustang \| Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, number of shares issued								16,877,638
Shelf Registration Statement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount available for future stock offerings							$ 86,200						86,200
Shelf Registration 2023 Statement [Member] \| Checkpoint
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount available for future stock offerings							77,700						77,700
Shelf Registration 2023 Statement [Member] \| Maximum \| Checkpoint
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, aggregate offering permitted by the agreement				$ 150,000
Shelf Registration 2024 Statement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount available for future stock offerings															$ 50,000
Shelf Registration 2024 Statement [Member] \| Mustang
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, aggregate offering permitted by the agreement													37,500
Shelf Registration 2024 Statement [Member] \| Maximum \| Mustang
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, aggregate offering permitted by the agreement		$ 40,000
Shelf Registration 2021 Statement [Member] \| Mustang
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, aggregate offering permitted by the agreement						$ 200,000							4,400
Shelf Registration 2021 Statement [Member] \| Avenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount available for future stock offerings							$ 24,600						$ 24,600
Direct Offering [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, number of shares issued										3,303,305
Exercise price of warrants										$ 3.21
Unit Price Per Share										$ 3.33
Warrant expiration term										5 years
Sale of stock, net proceeds										$ 10,200
Direct Offering [Member] \| Checkpoint
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common shares - Registered direct offering										1,275,000
Stock offering, price per share										$ 1.805
Sale of stock, net proceeds										$ 12,600
Direct Offering [Member] \| Checkpoint \| Common Stock Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of warrants										$ 1.68
Warrant expiration term										5 years
Direct Offering [Member] \| Checkpoint \| Pre-Funded Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants issued										6,481,233
Number of shares called by warrants										1
Stock offering, price per share										$ 1.8049
Exercise price of warrants										$ 0.0001
Direct Offering [Member] \| Mustang
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock offering, number of shares issued							3,025,000						575,191
Number of warrants to purchase shares							3,105,000						3,105,000
Stock offering, price per share							$ 0.4099						$ 0.4099
Per share amount reduced from share price to calculate warrant price							0.001						0.001
Exercise price of warrants							$ 0.001						$ 0.001
Warrant expiration term							5 years						5 years
Warrants exercised, Number of shares							3,105,000
Stock offering, aggregate fees paid							$ 300
Sale of stock, net proceeds							$ 2,200
Shares issued (in percent)							2.50%
Direct Offering [Member] \| Mustang \| Unregistered warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants to purchase shares							6,130,000						6,130,000
Exercise price of warrants							$ 0.41						$ 0.41
Direct Offering [Member] \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants to purchase shares										3,303,305
Direct Offering [Member] \| Maximum \| Checkpoint
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants to purchase shares										7,756,233
Private Placement \| Avenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise of warrants for cash			$ 4,500
Private Placement \| Avenue \| Series A Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants to purchase shares			220,538
Private Placement \| Avenue \| Series B Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants to purchase shares			220,538
Private Placement \| Avenue \| January 2023 Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants to purchase shares			25,871
Exercise price of warrants			$ 116.25
Exercise price of warrants agreed by investor			$ 22.545
Fair value of warrants							$ 600						$ 600
Private Placement \| Avenue \| November 2023 Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of warrants to purchase shares			194,667
Exercise price of warrants			$ 22.545
Exercise price of warrants agreed by investor			$ 22.545
Fair value of warrants							$ 4,300						$ 4,300