Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity (Common Stock and Equity Offerings) (Narrative) (Details)

v3.21.1
Stockholders' Equity (Common Stock and Equity Offerings) (Narrative) (Details)
 1 Months Ended 12 Months Ended
Jun. 11, 2020
USD ($)
$ / shares
shares
Apr. 30, 2019
USD ($)
$ / shares
shares
Mar. 29, 2019
shares
Jul. 26, 2016
shares
Jul. 22, 2016
Nov. 30, 2019
shares
Apr. 30, 2019
$ / shares
shares
Dec. 31, 2020
USD ($)
item
$ / shares
shares
Dec. 31, 2019
USD ($)
$ / shares
shares
Dec. 04, 2020
shares
Nov. 11, 2020
$ / shares
shares
Nov. 10, 2020
shares
Dec. 04, 2019
USD ($)
Sep. 30, 2019
USD ($)
shares
Aug. 16, 2019
$ / shares
Aug. 15, 2019
shares
Jul. 13, 2018
USD ($)
Dec. 31, 2016
USD ($)
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Common stock, shares authorized               125,000,000 125,000,000 125,000,000 125,000,000 85,000,000   85,000,000   50,000,000    
Common stock par value (in dollars per share) | $ / shares               $ 0.0001 $ 0.0001   $ 0.0001       $ 0.0001      
Common stock, shares issuable               2,103,122 1,206,667                  
Preferred stock, shares authorized               2,000,000 2,000,000                  
Aggregate value of shares subscribed | $               $ 7,939,000 $ 4,923,000                  
Common stock, shares issued               70,920,693 39,403,519                  
Proceeds from issuance of common shares - Public Offering | $               $ 37,230,000 $ 31,625,000                  
Aggregate fees of stock issuance | $               $ 2,388,000 $ 2,088,000                  
Shares available for future sale under ESPP               259,144                    
Fortress Biotech, Inc [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Percentage of fully diluted equity       2.50% 2.50%     2.50% 2.00%                  
Expenses from related party transaction | $               $ 500,000 $ 500,000                  
Aggregate value of shares subscribed | $                                   $ 900
Issuance Related to Debt Financing [Member] | Fortress Biotech, Inc [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Issuance of common shares - Founders Agreement (in shares)     108,069           108,069                  
Percentage of fully diluted equity     2.50%           2.50%                  
At the Market Offering [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Common stock, shares issued                 3,500,000                  
Maximum value of shares authorized to sell at offering | $                                 $ 75,000,000.0  
Agent commission (as a percent)                                 3.00%  
Issuance of common shares (in shares)               17,600,000                    
Issuance of shares, price per share | $ / shares               $ 3.40 $ 6.42                  
Proceeds from issuance of common shares - Public Offering | $               $ 59,800,000 $ 22,500,000                  
Proceeds from issuance of Common Stock, net of offering costs | $               58,700,000 22,000,000.0                  
Aggregate fees of stock issuance | $               1,100,000 $ 500,000                  
At the Market Offering [Member] | Fortress Biotech, Inc [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Proceeds from issuance of common shares - Founders Agreement | $               $ 59,800,000                    
Issuance of common shares - Founders Agreement (in shares)               342,773 87,656                  
Percentage of fully diluted equity               2.50% 2.50%                  
Issuance of common shares recorded (in shares)               101,632                    
Proceeds from issuance of common shares - Public Offering | $               $ 59,800,000 $ 22,500,000                  
Public Offering [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Issuance of common shares (in shares) 10,769,231 6,875,000                                
Issuance of shares, price per share | $ / shares $ 3.25 $ 4.00         $ 4.00                      
Proceeds from issuance of common shares - Public Offering | $ $ 37,200,000 $ 31,600,000                                
Proceeds from issuance of Common Stock, net of offering costs | $ 34,800,000 29,500,000                                
Aggregate fees of stock issuance | $ $ 2,400,000 $ 2,100,000                                
Number of stock options exercised 686,373                                  
Public Offering [Member] | Fortress Biotech, Inc [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Proceeds from issuance of common shares - Founders Agreement | $               $ 37,200,000                    
Issuance of common shares - Founders Agreement (in shares)               286,390 197,656                  
Percentage of fully diluted equity               2.50% 2.50%                  
Proceeds from issuance of common shares - Public Offering | $               $ 37,200,000 $ 31,600,000                  
Over-Allotment Option [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Issuance of common shares (in shares) 1,615,384 1,031,250                                
Registration Statements [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Maximum value of shares authorized to sell at offering | $                         $ 100,000,000.0 $ 75,000,000.0        
Value of securities available for future issuance | $               $ 85,700,000                    
Common Shares                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Number of votes per share | item               1                    
Common Shares | Fortress Biotech, Inc [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Common stock, shares issuable                                   2,000,000
Class A Common Shares [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Number of shares converted                 (154,615)                  
Common stock, shares authorized               1,000,000                    
Director appointment right, period               10 years                    
Common stock, shares issued               845,385 845,385                  
Common Class B                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Number of votes per share | item               1.1                    
Common Class B | Fortress Biotech, Inc [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Number of shares converted       7,250,000                            
Common stock, shares issuable                                   7,000,000
Preferred Class A [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Preferred stock, shares issued               250,000 250,000                  
Preferred Class A [Member] | Fortress Biotech, Inc [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Percentage of fully diluted equity         2.50%                          
Number of shares issued in conversion       250,000                            
General and Administrative [Member] | Issuance Related to Debt Financing [Member] | Fortress Biotech, Inc [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Expenses from related party transaction | $               $ 400,000                    
General and Administrative [Member] | At the Market Offering [Member] | Fortress Biotech, Inc [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Expenses from related party transaction | $               1,500,000 $ 500,000                  
General and Administrative [Member] | Public Offering [Member] | Fortress Biotech, Inc [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Expenses from related party transaction | $               $ 900,000 $ 800,000                  
City of Hope National Medical Center ("COH") [Member] | Common Shares                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Number of shares issued in conversion           17,007 137,608                      
City of Hope National Medical Center ("COH") [Member] | Class A Common Shares [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                    
Number of shares converted           17,007 137,608   154,615