Quarterly report pursuant to Section 13 or 15(d)

Licenses Acquired - Additional Information (Detail)

v3.5.0.2
Licenses Acquired - Additional Information (Detail) - USD ($)
 1 Months Ended 3 Months Ended 9 Months Ended 12 Months Ended
May 11, 2015
May 31, 2016
Feb. 29, 2016
Oct. 31, 2015
Sep. 30, 2015
Jul. 16, 2015
Jun. 17, 2015
May 31, 2015
Apr. 28, 2015
Mar. 31, 2015
Feb. 28, 2015
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2016
Sep. 30, 2015
Dec. 31, 2015
Feb. 17, 2015
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Payments to Acquire Intangible Assets                           $ 350,000 $ 1,250,000    
Research And Development In Process                       $ 1,000,000 $ 1,895,000 3,143,000 10,882,000    
Stock Issued During Period, Value, Issued for Services                           2,000 1,000    
Research And Development Expense                       7,316,000 $ 9,073,000 21,416,000 $ 13,172,000    
Payments to Acquire in Process Research and Development       $ 200,000                          
Development Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due           $ 22,600,000         $ 10,700,000            
Sale Millstone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due           7,000,000         26,200,000            
NeuPharma [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Research And Development In Process                   $ 1,000,000              
NeuPharma [Member] | Clinical Development Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                   40,000,000              
NeuPharma [Member] | Regulatory Approvals To Commercialize The Products [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                   22,500,000              
NeuPharma [Member] | Sale Millstone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                   $ 40,000,000              
City Of Hope [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Marketability Percentage Of Invested Capital                   44.80%              
Payments for Fees                   $ 2,000,000              
Stock Issued During Period, Shares, Other                   1,000,000              
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent                   30.00%              
Share Price                   $ 0.147              
Stock Issued During Period, Value, Other                   $ 100,000              
City Of Hope [Member] | Development Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                 $ 1,500,000                
City Of Hope [Member] | Sale Millstone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                 13,000,000                
National Institutes of Health [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Payment of Upfront Milestone Fees           700,000                      
New Zealand Pharmaceuticals Ltd [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Reimbursement Revenue           600,000                      
Dana-Farber [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Shares Issued, Price Per Share $ 0.065                                
Stock Issued During Period, Shares, Issued for Services 500,000       136,830                        
Stock Issued During Period, Value, Issued for Services $ 32,500       $ 600,000                        
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners         5.00%               5.00%   5.00%    
Proceeds from issuance of Common stock                             $ 10,000,000    
Dana-Farber [Member] | First Commercial Sale Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                       21,500,000   21,500,000      
Dana-Farber [Member] | Additional Sales Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                       60,000,000   60,000,000      
Mustang Bio, Inc [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Research And Development Expense                       500,000 $ 1,500,000 500,000 1,000,000    
Royalty Guarantees, Commitments, Amount                       1,000,000   1,000,000      
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners                   10.00%              
Royalty Revenue                       300,000   1,300,000      
Mustang Bio, Inc [Member] | Development Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                   $ 14,500,000              
Mustang Bio, Inc [Member] | Financial Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                   2,000,000              
Escala Therapeutics, Inc [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Payment of Upfront Fees           $ 1,300,000                      
Teva Pharmaceutical Industries Ltd [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Payment of Upfront Fees                               $ 500,000  
Teva Pharmaceutical Industries Ltd [Member] | Regulatory Approvals To Commercialize The Products [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                       206,500,000   206,500,000      
Teva Pharmaceutical Industries Ltd [Member] | Clinical Development and Regulatory Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                       220,000,000   220,000,000      
Jubilant Biosys Ltd [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Research And Development In Process                       2,000,000          
Revenue Recognition Milestone Method, Payments Due                       87,500,000   87,500,000      
Payment Of Upfront Licensing Fee   $ 2,000,000                              
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners               50.00%                  
Jubilant Biosys Ltd [Member] | Regulatory Approvals To Commercialize The Products [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due   59,500,000                              
Jubilant Biosys Ltd [Member] | Successful Achievement Of One Preclinical Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                       300,000   300,000      
Jubilant Biosys Ltd [Member] | Completion Of Three Clinical Development Milestones For Two Licensed Products [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                       25,500,000   25,500,000      
Jubilant Biosys Ltd [Member] | Five Regulatory Approvals And First Commercial Sales [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                       61,700,000   61,700,000      
Jubilant Biosys Ltd [Member] | Three Sales Milestones Based On Aggregate Net Sales [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                       89,000,000   89,000,000      
Jubilant Biosys Ltd [Member] | Sale Millstone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Milestone Method Revenue Additional Payments Eligible To Receive   89,000,000                              
Jubilant Biosys Ltd [Member] | Clinical Development and Regulatory Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due   $ 89,000,000                              
Jubilant Biosys Ltd [Member] | TG Therapeutics, Inc [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Payment Of Upfront Licensing Fee                           1,000,000      
Collaboration Agreement with TGTX [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Payments for Fees                       0 25,000 20,000 500,000 $ 500,000  
Triplex [Member] | City Of Hope [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Minimum Annual Royalty Payable                 750,000                
Triplex [Member] | City Of Hope [Member] | Development Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                 9,000,000                
Triplex [Member] | City Of Hope [Member] | Sale Millstone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                 26,000,000                
Pentameter [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Minimum Annual Royalty Payable                 750,000                
Pentameter [Member] | City Of Hope [Member] | Development Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                 5,500,000                
Pentameter [Member] | City Of Hope [Member] | Sale Millstone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                 26,000,000                
Coronado SO Co, Inc [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Research And Development In Process                       $ 0 $ 0 $ 0 $ 1,607,000    
Payments for Fees                     $ 900,000            
Stock Issued During Period, Shares, Other                     150,000            
Research And Development Expense       $ 500,000                          
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners         13.00%             13.00% 13.00% 13.00% 13.00%    
Checkpoint Therapeutics, Inc [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Research And Development In Process                       $ 1,000,000 $ 600,000 $ 3,060,000 $ 2,633,000    
Reimbursement Of Cost Recognized As Revenue                       $ 251,000   $ 732,000      
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners         20.00%             62.70% [1] 20.00% 62.70% [1] 20.00%    
Checkpoint Therapeutics, Inc [Member] | First Commercial Sale Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                       $ 21,500,000   $ 21,500,000      
Checkpoint Therapeutics, Inc [Member] | Additional Sales Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                       60,000,000   60,000,000      
Checkpoint Therapeutics, Inc [Member] | Clinical Development Milestone [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                       7,000,000   7,000,000      
Checkpoint Therapeutics, Inc [Member] | Commercial Sales In Specified Territories [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Revenue Recognition Milestone Method, Payments Due                       14,500,000   14,500,000      
Helocyte [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Research And Development In Process                 200,000     $ 0 $ 0 83,000 $ 200,000    
Research And Development Expense                           $ 35,000      
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners                       20.60%   20.60%      
Licensing Agreements [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Payments to Acquire Intangible Assets     $ 35,000           $ 50,000 $ 155,000              
Licensing Agreements [Member] | City Of Hope [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Marketability Percentage Of Invested Capital                           44.50%      
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent                           30.00%      
Share Price                       $ 0.097   $ 0.097      
Stock Issued During Period, Value, Other                           $ 48,500      
Licensing Agreements [Member] | City Of Hope [Member] | Common Class A [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Noncash or Part Noncash Acquisition, Noncash Financial or Equity Instrument Consideration, Shares Issued   500,000                              
Licensing Agreements [Member] | Dana-Farber [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Payments for Fees               $ 1,000,000                  
Licensing Agreements [Member] | Coronado SO [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Marketability Percentage Of Invested Capital       44.80%                          
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent       30.00%                          
Share Price       $ 1.19                          
Licensing Agreements [Member] | IV Tramadol [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Payments to Acquire Intangible Assets             $ 1,000,000                    
Payments for Fees                     $ 2,000,000            
Licensing Agreements [Member] | Helocyte [Member] | Common Class A [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Noncash or Part Noncash Acquisition, Noncash Financial or Equity Instrument Consideration, Shares Issued   8,333                              
Avenue Therapeutics, Inc. [Member]                                  
Research and Development Arrangement, Contract to Perform for Others [Line Items]                                  
Shares Issued, Price Per Share                               $ 0.146  
Research And Development Expense                       $ 2,500   $ 11,500      
Debt Instrument, Fee Amount                                 $ 3,000,000
[1] Checkpoint is consolidated with Fortress’ operations because Fortress maintains voting control through its ownership of Checkpoint’s Class A Common Shares which provide super-majority voting rights.